INVEKTEBRATA, CRYPTOGAMIA, MICROSCOPY, ETC. 269 



opposed across the dorsal surface, or with only a few rudimental ones 

 in its anterior part, or with a single very large one, resembling a 

 broad, branched or unbranched lobe, and near to it some small 

 papillcB. No respiratory trees. Integument naked, spiculous, or 

 plated. 



In the first part of a preliminary report on the ' Challenger ' 

 Holothuridea,* Dr. Theel defines seven new genera (with nine new 

 species) of Elasmopoda, viz : — 



Deima (Set/xa, a fright), 2 sp. 

 Oneirophanta (dveLpucfiavTa, a vision), 1 sp. 

 Orphnurgus {opt^vrj, darkness), 1 sp. 

 Gryodora (/cpu'os, cold), 1 sp. 

 Lcetmogone (Aatr/xa, dej^ths of the sea), 2 sp. 

 Ilyodoemon (l\.v^, ooze, Sat/xwv, spirit), 1 sp. 

 Achlyonice ( a.)(kv<;, darkness), 1 sp. 



There are also described six new species of Elpidia (iX-n-i^, hope), 

 one of Irpa, and one of Kohja (names from the Norse mythology), 

 the two latter being new genera closely related to Elpidia, procured 

 by the Norwegian North-Sea Expedition, and described by Keren 

 and Danielssen. 



These are all abyssal forms, eight of the seventeen species having 

 been dredged from depths of more than 2000 fathoms. They are 

 very extravagant in sliape — the names which Dr. Theel has given 

 them shows that their appearance suggests " such stufi" as dreams are 

 made of " — and they are of large size, some over a foot in length. 



One group is very gelatinous, and of a rich purple colour ; others 

 are gelatinous, grey, and semi-transparent ; while another series, and 

 among these the most fantastic of the whole, are yellowish and liave 

 a test crustaceous with a thick layer of calcareous plates, often 

 running out into strangely shaped processes. A peculiar little group 

 from the Antarctic Sea are little more than a gelatinous membrane, 

 covering an enormously distended intestine, filled with diatom ooze. 

 From the number of species and individuals which came up in the 

 scattered and infrequent hauls of the trawl, the Elasmopoda must 

 form. Sir Wyvillo thinks, quite a prominent feature of the abyssal 

 fauna. 



Nervous System of Comatula.t — Mr. P. H. Carpenter points out 

 tliat altliough tliero is a close histological resemblance between the 

 ambulacral nerves of the Star-fishes and Crinoids, there is one imjiortant 

 point of difiercnce between thc;m. The ambulacral nerves of tlic 

 star-fishes — at any rate of the Ophiurids — send ofi" branches to tho 

 muscular bundles which connect successive joints of the rays and 

 ctfect the movements of the animal. The swimming movements of 

 Comatula are far more active tlian tho movements of any star-fish, 

 and are also performed with a singular regularity, while they are 

 cflcctud by tho combined contraction of several hundred pairs of 



* ' lliiu.ll. K. SvcMbk. Vct.-Akud..' v. No. 19. 

 t ' Kcp. Brit. Assoc. Adv. Sci.,' l.S7i), p. lib". 



