﻿CRl'STAClvA MAJ.ACOSTRACA. II. 



area is more difficult to define, Init it iiia\' be proposed that the stations witli a depth between 300 

 and 600 fathoms and the l)ottom temperature not below 3", and all stations with depth from 600 to 

 1870 fathoms and the temperature above zero belong to tliat area. Wlicn we adojjt tliis view it will 

 be found that about 38 species enumerated in the following pages were taken e.\chisi\ely in lliis 

 warm deep-sea area, which consequenth' has a much richer fauna than the ccjld deep-sea area. A 

 somewhat small number of species (Sphyrapiis (ii/a/iitili/s (i. (). .S., rsiudoiiuiais a /finis H. J. H., Tvpiilu- 

 fdi/ais inixtns n. sp. Lipioi^niai/iiu loi/i^iiu-iiiis Lilljcborg, /,. vtiilnilis n. sp., L. brrvinniis Lilljebg., 

 Cr\ptocopc arctica H. J. H. and Styoiigyliira lyliiidrohi G. O. S.) have been taken both in the real cold 

 deep-sea area and at rather deep or very deep stations in the warm area; but with a single 

 exception ['ryplilotiuiais mix I in] all these species have besides been taken in de])tlis of less than 

 100 fathoms either by the "Ingolf" or at Norwa>-, at East Greenland or in the Kara vSea. The 



majorit\' of the remaining species are forms living in depths less than 300 and frequcntl\' less than 

 100 fathoms. Some few species (as Lipfogi/afiiia iiitrinis \\. sp., L. Sarsii H. J. H.. L. sultifqudlis n. sp. 

 and L.latirniiis n. sp.) cannot be referred to any of the three categories just mentioned, but they seem 

 to be essentialh' cold water forms sometimes found in temperatures a little above zero; L.snlxcqnalis 

 was once taken e\en in 318 fathoms in a temperature of 3.9". 



C. Sexual Differences in the Tanaidae. 



Adult males of species of the famih' Apseudidte are frequenth taken together with the 

 females, and I am unable to add anything to our knowledge of the se.xual differences in this family. 

 Sars has published e.xcellent figures of both sexes of the two Norwegian species Apscndrs spiiiusus 

 M. Sars and Spiiynipus niioiinilns G. O. vS., of Spi/yrnpi/s si-rnif/is (\. G. .S. and of a few species of 

 Apscndrs from the iMediterranean. In the males the abdomen is generally longer in proportion to 

 the thoracic segments, the pleopods and their set:e are longer, the flagella of the antennuke and 

 antennae and the endopod of the uropods are longer and divided into a larger number of joints than 

 in the females; furthermore, the chelipeds of the males differ somewhat or ver\- much from those 

 of the females, and sometimes the second pair of thoracic legs show some difference. 



As to the familv Tanaitke our knowledge of the males is still very imperfect and .some inter- 

 pretations are erroneous; it is necessary to distinguish sharph' between adult and subadult or immature 

 males. Sars has described the females of 26 species of Tanaid;e from Xorwax', but he was acquainted 

 with really adult males of only 5 species, viz. Tmiais Covoliiiii ,M.-Kdw. {'!'. loinnitosus Kr., G. O. S.), 

 Hctcrotanais Uersfcdii K.r., Typliloiauais pniiian-liicus G. O. S., I'arataiiais Bii/ri V,A).':~>. and l.tptoiiiiatltia 

 .S>7rw H. J. H. (L. loiiginiiiis G. O. S.. not Lilljeborg); he described also what he believed to be the 

 males of Aimrtlinini siinplrx G. U. S. and /'sriidofai/nis /orcipa/iis Lilljebg., hut his animals were only 

 subadult males, not adult specimen.s, and at least the adidt male of the last-named species (already 

 described, without figures, b\- ],illjel)org) is widely different from the subadult stage. Sars was aware 

 that his males of S/roi/i^v/iini ryliiidniln G. ( ). vS. were "probabK" inunature, which in rcalitv was 

 the case. In i<S85 Ik- figured the adult male of Crypiocopr ]liriiii(ii (">. O. S.; in his paper on the 

 Mediterranean lornrs he figured the adult males of [.rptoi^iiatiiia hiuvinnnia T.illjebg.. //r/fro/oiiais 



