Sea of Cortez

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Sea of Cortez Page 27

by John Steinbeck


  The Western Flyer hunched into the great waves toward Cedros Island, the wind blew off the tops of the whitecaps, and the big guy wire, from bow to mast, took up its vibration like the low pipe on a tremendous organ. It sang its deep note into the wind.

  A NOTE ON PREPARING SPECIMENS

  Following are the methods of preparing, anesthetizing, and preserving specimens which we have followed. As previously remarked, some are by no means entirely satisfactory, but they are the best we know.

  The chitons, which otherwise curl up tightly during preservation, can be removed directly from rock or collecting bucket and tied firmly to glass plates with string or strips of cloth. When they grip the plate, they are dropped into a container of ten-percent formalin; whereupon they are preserved relaxed.

  Sipunculids (or peanut worms), to be preserved with the introvert extended, must first be anesthetized by sprinkling powdered menthol crystals on the sea water in a scrupulously clean glass dish. These worms are so delicate that metal or metal salts will cause them to draw in their heads immediately. The more refractory forms, after a few hours’ treatment with menthol, are killed by letting fresh water gradually replace the sea water. This must be done over a period of several hours. They are then preserved in formalin solution.

  Alcyonaria, such as Renilla (the sea-pansy), Stylatula (the sea-pen), etc., are treated with Epsom salts for several hours until the expanded polyps are completely inert, then preserved in formalin if they are intended for display where color is important (although even thus the color is not successfully retained) or in alcohol if for study or identification.

  Hydroids are relaxed with menthol for the small forms, with Epsom salts for the large gymnoblasts.

  Anemones are very difficult to handle, and a perfect method for expanding them has not been developed. They are sensitive both chemically and physically. A specimen expanded and relaxed with Epsom salts will still draw in its tentacles if touched. Some results have been achieved by introducing pure oxygen directly into the stomach with a tiny hollow glass needle—a process which seems to intoxicate them. But it is at best a delicate and over-arduous operation. A fairly good method is gradually to introduce a saturated solution of Epsom salts into the pan where the animals are expanded, using a drip-string. This is followed later with novocain, or best of all, but usually unavailable, with cocaine, which is put into the water directly over the animal. Finally, formalin is introduced with a drip-string. Any shock, either chemical or physical, will cause immediate retraction of the tentacles. For permanent use a running seawater system which supplies O2 to the circulation of the animals being narcotized has proven most effective of all.

  Crabs and shrimps of most types, and brittle-stars, are best killed by dropping them into fresh water as soon after they are captured as possible. After a brief struggle the crabs die without casting their legs, and the brittle-stars (with the exception of Ophioderma teres) will not curl up if this method is used. All these should subsequently be preserved in alcohol, since formalin will disintegrate the calcareous portions of the brittle-stars and soften the chitin of the crabs. For color notes only, specimens may be preserved in formalin.

  Holothurians (or sea-cucumbers) are very delicate and have a tendency to eviscerate if kept in stale or over-warm water. They should be got as soon as possible into trays of cool, clean sea water, allowed to expand, then relaxed with Epsom salts used in considerable quantity. They should be preserved in alcohol. Most holothurians deteriorate badly in a few months if formalin is used on them, owing to the dissolution of the calcareous plates by which specialists determine them. Their neurotic tendency of deliberately casting out their viscera when they are sick or shocked or unhappy makes them difficult to handle. The cucumber itself, if times get better and a pleasant environment is restored, is able to grow a new set.

  Starfish relax and puff out in a life-like manner when placed for several hours in fresh water. They can ordinarily be preserved in formalin, but museum specimens for determination should be placed in alcohol for a time and dried in the air. This method also applies to sea-urchins.

  Sponges must not be placed in formalin even for a few moments. Entire colonies can be dried after a preliminary immersion in alcohol; small portions of the colonies so treated ought, however, to be preserved permanently in a vial of alcohol.

  Flatworms such as the turbellarians are hard to collect, hard to handle, and hard to preserve. They are so delicate that the bodies are easily injured in picking them up. When they are crawling on a rock it is satisfactory to place a thin-bladed knife in their path; when the flatworm oozes onto the knife-blade he can be lifted into a container. Very small specimens may be lifted from the rock with a camel‘s-hair brush and transported to a glass plate. This is flooded with hot Bouin’s solution and immediately covered with another glass plate. If one could devise smooth plates permeable by Bouin’s solution it would be even better.

  Several methods are applicable to the preservation of such pelagic invertebrates as jellyfish. Menthol crystals are a successful anesthetic for the contractile forms. However, the difficulties are likely to relate to the extreme softness of the more delicate forms. Hardening solutions of chromic acid and formalin, or osmic acid (which, however, is very expensive—five to six dollars a gram) in formalin, are most effective. Often there are mechanical difficulties involved in attempts to retain the original shapes of animals. The jellyfish Beroë tends to buckle up. We have had some success by inserting the closed end of a test-tube in the body cavity during the hardening process. It is really impossible to preserve jellyfish aboard a boat that is rolling even slightly. Formalin is usually a satisfactory preservative, and is often indicated exclusively.

  It seems from these notes that all animals are difficult to preserve, and it is true that all of them require care which is not often enough given. The almost universal cry of specialists engaged in species determination is that specimens arrive in such bad condition that their work is made doubly difficult. Only extreme care can rectify this.

  Some of the annelid worms are extremely difficult to handle. Anesthetizing methods are useful, but the delicacy of the animals and their constricting traits make special procedure necessary. Very long specimens may be wrapped around glass rods or test-tubes and suspended in formalin or alcohol, depending on the species. The chief difficulty with worms is to get the entire animal in the first place, especially the extreme anterior and posterior segments without which identification is difficult if not impossible. Some of the worms sting very badly and should not be handled at all.

  For the preservation of fishes, formalin in general gives better results than alcohol. Small specimens are hardened by putting them directly into trays of formalin solution; while larger fishes must have the body cavities injected with a twenty-to twenty-five-percent solution of formalin to which a little glycerin has been added.

  Formalin should be used as follows: U.S.P. formaldehyde solution of thirty-eight to forty percent is a gas dissolved in water, and this percentage represents saturation. One part of this to sixteen parts of water for small specimens is successful when the amount of the solution is many times the bulk of the animal. Large specimens are hardened in trays of ten- to fifteen-percent solution. One must check by experiment on the particular animal involved, feeling it after a few hours to note the consistency of the tissue. Formaldehyde is very irritating to nose, lungs, and skin. Rubber gloves should always be used and the solution worked with in large rooms or in the open air. The tolerance of a person working with formaldehyde sometimes decreases with time, so that he is sickened at the odor or even breaks out with allergy eruptions on contact or association.

  With alcohol the ultimate preservation is usually in seventy-percent strength. For crabs and so forth in the tropics or in very hot weather, glycerin should be added. This keeps the animals flexible and less brittle—less likely to break up—and also prevents poor preservation due to bubbles forming in the solution. For ideal preservation the spec
imen should be brought immediately after killing into a twenty-five-percent solution, then to fifty percent and finally to seventy percent. Large specimens, where the amount of liquid is small in proportion to the amount of tissue involved, may require ninety-percent solution for a few days of hardening before they are placed in a new seventy-percent solution.

  Labeling is easy, simple, and necessary. Yet the failure to label clearly and immediately has led to many ridiculous situations. One expedition, which need not be named, labeled Atlantic animals as coming from the Panamic regions. And another completely lost track of its collection, to the disgust of the specialists who later tried to determine the species. Labels are best made on slips of good drawing paper and printed with a drawing pen in India ink. Each label should include the date, the exact place, the depth, and a number added which will agree with the number in the collecting notes. In the collecting notes, under this number, should occur any remarks covering ecological factors or observed action of the living animal which would be impossible to put on the label. The label should be placed inside the jar with the animal, and it should be done immediately, before a new lot of specimens comes in. There has not, to our knowledge, been any single expedition or extended trip which failed to turn out some unlabeled, or mislabeled material, so that the records are full of obviously incorrect reports. Some Panamic animals have been reported from Puget Sound, and our common California shore crab, Pachygrapsus, was originally described as from the Sandwich Islands. Immediate labeling, on the same day as the collection, is the only way to reduce these errors to a minimum. This cannot be over-emphasized.

  Fig. 1. Phyllonotus bicolor (Valenciennes ) 1852 § S-358 Pink Murex

  Fig. 1. Murex rectirostris Sowerby. Gulf spiny Murex § S-355

  Fig. 2. Cerithium maculosum Kierner § S-374

  The Spotted Cerithium

  Fig. 1. Thais tuberculata Gray. Knobby Thais § S-367

  Fig. 2. Phyllonotus princeps (Broderip) § S-361

  Regal Murex

  Fig. 1. Protothaca grata (Sowerby) § S-252

  Varicolored Edible Clam

  Fig. 2. Cypraea annettae Dall 1909. Brown Cowry § S-370

  Fig. 1. Terebra variegata Gray 1834 § S-326

  Variegated Augur-shell

  Fig. 2. Nassarius ioaedes and luteostoma § S-340 and § S-341

  Fig. 1. Callopoma fluctuosum (Wood) 1828 § S-404

  Common Gulf Turbine-shell

  Fig. 2. Oliva venulata Lamarck § S-331

  Gulf Olive-shell

  Fig. 1. Gulf Olive-shell. Albino color variety § S-331

  Fig. 2. Chiton virgulatus Sowerby 1840 § U-17

  Common Gulf Chiton

  Fig. 1. Strombus gracilior Sowerby 1825 § S-372

  Smooth Conch

  Fig. 2. Melongena patula § S-338

  Broderip and Sowerby

  Fig. 1. Ophiocoma alexandri Lyman 1860 § K-215

  ½ natural size

  The drawings on plates 9-24 inclusive are by Alberté Spratt

  Fig. 1. Nidorellia armata (Gray) 1840 § K-126

  natural size, 5½“-6” oral surface

  Fig. 2. Holothuria impatiens (Forskål) 1775 § L-21

  ½ natural size

  Fig. 1. Oreaster occidentalis Verrill 1867 § K-125

  natural size, 6”

  Fig. 2. Nidorellia armata (Gray) 1840 § K- 126

  natural size, 5½“-6” aboral surface

  Fig. 1. Petrochirus califomiensis Bouvier 1895 § Q-16

  ¾ natural size

  Fig. 2. Tedania ignis (Duchassaing and Michelotti) 1864 § A-23

  ½ natural size

  Fig. 1. Ophiocoma acthiops Lütken 1859 § K-214

  aboral surface. ½ natural size

  Fig. 2. Dentalium semipolitum Broderip and Sowerby § S-103 and 104 and D. splendidum Sowerby 1832 1¼ natural size

  Fig. 1. Ocypode occidentalis Stimpson 1860 § R-75

  ½ natural size

  Fig. 2. Callinectes bellicosus Stimpson 1859 § R-42

  ½ natural size

  Fig. 1. Phataria unifascialis (Gray) 1840 § K-120

  ½ natural size

  Fig. 2. Ophiactis sp.

  1½ natural size

  § K-218 (219?)

  Fig. 3. H. lubrica Selenka 1867

  Sulphur cucumber § L-25

  ½ natural size

  Fig. 4. Luidia pbragma Clark 1910 §K-128

  natural size, 4½“-5”

  Fig. 1. Clibananus panamensis § Q-14

  Stimpson (1859) 1862 natural size

  Fig. 2. Phycosoma antillarum (Grube and Örsted) 1859 1-10 natural size

  Fig. 3. Othilia tenuispina (Verrill) 1871 as Echinaster § K-124

  Fig. 1. Clypeamr rotundus (A. Agassiz) 1863 § K-322

  ½ natural size

  Fig. 2. Echinometra vanbrunti A. Agassiz 1863 § K-314

  ½ natural size

  Fig. 1. Eurythoë complanata (Pallas) 1766 § J-35

  ⅔ natural size

  Fig. 2. Geograpsus lividus § R-68

  (Milne-Edwards) 1837 ½ natural size

  Fig. 3. Portunus minimus § R-40

  Rathbun 1898 natural size

  Fig. 4. Eriphia squamata § R-58

  Stimpson 1859 1½ natural size

  Fig. 5. Daira americana § R-45

  Stimpson 1860 natural size

  Fig. 6. Trapezia cymodoce ferruginea

  Latreille 1825 1½ natural size § R-60

  Fig. 1. H. paraprinceps § L-26

  Deichmann 1937 ½ natural size

  Fig. 2. Meoma grandis Gray 1852 § K-324

  ½ natural size

  Fig. 3. Astropyga pulvinaca (Lamarck) 1816 § K-318

  Fig. 1. Pharia pyramidata (Gray) 1840 § K-119

  Fig. 2. Chloeia viridis § J-34

  (Schmarda) 1861 ⅔ natural size

  Fig. 3. Notopygos ornata

  Grube 1856 § J-36

  natural size

  Fig. 1. Evibacus princeps § P-105

  Smith 1869 ¾ natural size

  Fig. 2. Callopoma fluctuosum § S-404

  (Wood) 1828 natural size

  Fig. 3. Pocillopora capitata Veirill 1864 § E-7

  ¾ natural size

  Fig. 4. Hypoconcha panamensis

  Smith in Verrill 1869 § R-25

  ¾ natural size

  Fig. 5. Pontonia pinnae Lockington (1878) 1879 natural size § P-25

  Fig. 6. Percnon gibbesi § R-74

  (Milne-Edwards) 1853 natural size

  Fig. 1. Eucidaris thouarsii § K-313

  (Valenciennes in L. Agassiz and Desor) 1846

  ½ natural size

  Fig. 2. Petrolisthes edwardsii (Saussure) 1853 § Q-27

  ½ natural size

  Fig. 3. Cliona celata Grant 1826 § A-13

  ⅓ natural size

  Fig. 1. Leucetta losangelensis A-18

  (de Laubenfels) 1930 ½ natural size

  Fig. 2. Arbacia incisa § K-315

  A. Agassiz 1863 ½ natural size

  Fig. 3. Mithrodia bradleyi Verrill 1867 ½ natural size § K-122

  Fig. 1. Heliaster kubiniji Xantus 1860 § K-116

  Fig. 2. Thoë sulcata § R-32

  Stimpson 1860

  PHOTO BY HAMJUOD L. SWIFT

  Fig. 3. Mellita longifissa Afichelin 1858 1½ natural size § K-323

  Fig. 1. Cerithidea mazatlanica Carpenter 1857 § S-373

  Mazatlan Horn-shell

  PHOTO BY HARLAND L. SWIFT

  Fig. 2. Octopus sp. upper surface

  Diameter of body 49.1 mm.

  Fig. 3. Octopus sp. under surface

  § U-116

  PHOTOS BY WILLIAM G. VESTAL

  Fig. 1. Pilumnus gonzalensis § R-52

  Rathbun 1893

  Fig. 2. Pilumnus townsendi § R-54

  Rathbun 1923

  PHOTO BY HARLAND L. SWIFT

  Fig. 3. Siphonaria pica Sowerby. Starry Pulmonate § S-325

  Limpet, under surface

 

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