146 



NA TURE 



\_Dec. 17, 1885 



appearance. They are attached comparatively close 

 together, in a vertical position, with the convex surface 

 turning in and the concave out ! Of any specific ocular 

 pigment, or indeed of any visual elements whatsoever, no 

 trace could be detected in the recently-taken specimens, 

 and subsequent examination fully confirmed the absolute 

 want of such " (p. 57). 



One species of Cumacea, Diastylis nodosa., was obtained 

 in 125 fathoms at Ice Sound, Spitzbergen. It has no 

 trace of eyes, the ocular tract being quite flat, nor can 

 any pigment or other visual element be seen (p. 63). 



Of the ISOPODA 18 species are recorded, including 

 members of the families ApscudidiT, Taiia'di?, Anceida, 

 and Arcturida. 



Sptiyrapus serratits, Sars, is one of the most remark- 

 able of these, both in the form of its body, of which 13 

 somites can be seen, and 19 paired appendages (Plate 21). 

 The first pair of legs springing from the posterior part of 

 the cephalic segment, are like the chelipeds in more 

 highly-developed Crustaceans (Decapods), exceedingly 

 powerful prehensile organs. The second pair of legs are 

 as long as the entire body, and are flattened and armed 

 with powerful spines, as if intended to serve as fossorial 

 organs. Five pairs of slender walking appendages follow, 

 succeeded by five pairs of biramous swimming-feet and a 

 pair of long multiarticulate caudal appendages, also 

 branched. The whole appearance of this creature is 

 most remarkable, but it has a strong resemblance to 

 Apseudcs. 



Sphyrapiis seri-atiis occurs in the open sea between 

 Norway and Iceland, and also west of Spitzbergen, vary- 

 ing in depth from 1163 to 1333 fathoms, and ranging from 

 the 63rd to the 7Sth parallel of latitude. Eyes, in a strict 

 sense, are entirely wanting ; no trace of visual elements 

 whatever could be detected (p. 6S). Of the Tanaida, 

 three species, belonging to as many genera, were taken ; 

 all in deep water and all blind (Plate 7). The colour of 

 these forms, as a rule, is a uniform white. 



Not least remarkable among the Isopoda are the 

 Anceida (Plate 8), most insect-looking of all the Crusta- 

 cea ! " The so-called mandibles (Fig. 6), which, however, 

 as pointed out by Prof Dohrn, both as regards their 

 position relative to the buccal orifice and their general 

 development, can scarcely be held to be homologous with 

 the mandibles in other Crustaceans, are attached to the 

 foremost margin of the head, and project freely in front 

 of it, admitting of being moved horizontally one towards 

 the other, like a pair of forceps " (p. 88). The larvx 

 (Praniza) are even more insect-like in appearance than 

 the adult forms (see Plate 8, Figs. 13 and 27). The 

 females of these forms are probably parasitic upon deep- 

 sea fishes, or other large deep-sea animals. The males 

 and larvK of three species described were dredged from 

 72° to7S°N. lat., in from 658 to 1215 fathoms ; they are 

 all blind forms. 



Many beautiful forms of Arcturida:, e.g. Arcturtis 

 baffi7ii, A. tuberosiis, A. hysttix, i&c, are figured and 

 described. A. baffini was taken as far north as the west 

 coast of Spitzbergen in 416 fathoms, and Glyptonotus 

 megalurtcs, an allied form ranging from 63° to 78° N. 

 latitude, inhabits depths of from 108 1 to 17 10 fathoms in 

 ice-cold water ! 



Another strange form is the Eiirycopc gigantea. In 



this isopod the 2nd pair of antennae are prodigiously 

 developed, being more than four times the length of the 

 whole body. 



The Amphipoda, 45 in number, form by far the largest 

 group of Crustacea obtained by the Expedition. 



Harpinia abyssi (G. O. Sars, PI. 13, Fig. 5) was ob- 

 tained from a depth of from 350 to 2215 fathoms ! It is 

 distributed from 63° to 75° N. latitude and from 16° E. 

 long, to 12° W. long. Epimeria loricata, a very hand- 

 some form, with spinose segments (PI. 14, Fig. 2) was 

 dredged near Spitzbergen in 260 fathoms. Oidiceros 

 macrocheir dredged off Jan Mayen in 1004 fathoms was 

 destitute of eyes (PI. 1 5, Fig. 4). Melita pallida, another 

 blind form (PI. 15, Fig. i), was found inhabiting deserted 

 T^n'^/y-burrows in an old piece of wood, dredged up 

 from a depth of 1333 fathoms off the west coast of 

 Spitzbergen. 



Several Caprellce, attached to hydroid polyps, were 

 brought up in the dredge from a rocky bottom at 180 

 fathoms. 



Eucheta norvegica, a copepod of the family Calanidce 

 was taken at no fewer than twelve stations at 'oery con- 

 siderable depths, whereas the surface-net at these locali- 

 ties, even when sunk considerably below the upper layer, 

 never contained a single example. 



Of the Cirripedia, Scalpelliim strbmii was dredged in 

 870 fathoms attached to the tubes of Tubularia indivisa. 

 Five other species were obtained, namely, Js'. cornutum, 

 S. hamatuin, S. vulgare, S. angustum, and S. striolatutn, 

 the last attached to sponges. These are mostly white, 

 and were collected from numerous localities and from 

 varying depths. 



A remarkabl)' slender tubular form of Balanus crcnatus 

 was met with in 21 fathoms north of Beeren Island. 



A Rhizocephalon (fam. Pelto^astridti) named Stylon 

 Hymenodore attached parasitically to the abdomen of 

 Hymenodora glacialis (dredged from a depth of 1S61 

 fathoms) completes the list of forms described. 



Thirteen additional species are referred to in a supple- 

 ment as noticed by other writers since the present work 

 was handed in to the scientific editor. 



One is struck by the fact that of the 82 species of 

 Crustacea obtained by Sars, at these great depths in this 

 ice-cold area, 61 are considered to represent distinct 

 genera ! Can it be that the conditions of life are here so 

 hard, and the struggle for existence so severe, that each 

 individual peculiarity becomes intensified, and that not 

 only the cold, but the darkness may produce considerable 

 changes in their organisation ? Absence of colour and 

 absence of sight are the prevailing characteristics ex- 

 hibited by nearly every species ; whilst the loss of eyes 

 seems to stimulate the development of all the tactile 

 organs to supply their place, so that we find the same 

 idiosyncrasies of structure manifested in these depths of 

 the ocean as have been observed in the Crustacea of the 

 American and Austrian caves, and from the dark under- 

 ground waters of various parts of the world. 



We should fail in our duty to the author and also to the 

 scientific reader did we omit to point out for high com- 

 mendation the admirably-prepared plates which accom- 

 pany Prof Sars' Memoir, all the details of which are 

 most beautifully and accurately rendered. 



And lastly, but by •:.^ means the least meritorious feature 



