March 12, 1886.] 



SCIENCE. 



249 



intellect strike one as being predominantly ab- 

 stract. — a result, doubtless, of their long life in 

 cities, and exclusion from nature on the one side, 

 and from the education which lies in handicrafts on 

 the other. We may expect great mathematicians 

 and philosophers from them, but not great in- 

 ventors, biologists, or painters, till they have had 

 time to throw off the effects of then- long seclu- 

 sion from nature. 



RECENT CHALLENGER REPORTS. 



Report on the Schizopoda tvol xiiU. By Prof. G. O. Sars. 

 London, Government, 1885. 4°. 



The Schizopoda and Cumacea collected during 

 the voyage of the Challenger were placed in the 

 hands of Professor Sars of Christiania for ex- 

 amination and description, and very wisely, for he 

 had done more to elucidate these groups than all 

 other authors combined. This report, by far the 

 most important addition yet made to our knowl- 

 edge of the Schizopoda, more than justifies the 

 English authorities in intrusting certain portions 

 of the Challenger collections to foreign natural- 

 ists. Fifty-seven species of Schizopoda, repre- 

 senting twenty-one genera, are here fully de- 

 scribed and very carefully and elaborately figured 

 by the author himself, who says very truly that 

 the collection " has turned out extremely rich, 

 and of very special interest ; " but this result is 

 undoubtedly very largely due to the great care 

 with which Professor Sars has examined the mis- 

 cellaneous material collected in surface-nets, and 

 submitted to him. Forty-six of the fifty-seven 

 species were first made known by the Challenger 

 expedition, and the elaborate working-out of this 

 large number of new forms from widely different 

 regions and depths affords most important new 

 material for discussing the proper subdivision of 

 the Schizopoda and their relation to the other 

 Crustacea. 



Professor Sars, I am glad to see, regards the 

 Schizopoda as a suborder distinct from but closely 

 allied to the Decapoda proper, and retains with 

 them the Euphausiidae, in spite of Dr. Boas' argu- 

 ments that they should be regarded as a distinct 

 order. He also shows that the genus Eucopia, 

 which has been referred to the Penaeidea by Dana 

 and Bate, is a true schizopod, though representing 

 a distinct family. Thus we have four families of 

 Schizopoda : Lophogastridae, Eucopiidae, Euphau- 

 siidae, and Mysidae. 



The Lophogastridae, which, previous to the 

 Challenger expedition, was represented by a 

 single genus, is here augmented by the remarkable 

 genus Gnathophausia and two new genera. Of 

 Gnathophausia, which was first made known by 

 Willemoes-Suhm during the progress of the ex- 



pedition, and contains the largest known schizo- 

 pods, no less than nine species are here described, 

 one of them over six inches in length. The 

 anatomy of the genus is carefully worked out, and 

 its affinities to Lophogaster well shown. All the 

 species of the family appear to be inhabitants of 

 deep water. 



The account of the Euphausiidae is the most 

 important and interesting part of the work. 

 Nearly all the species of this family are pelagic 

 in habits ; and Professor Sars* careful examination 

 of the surface collections made on the expedition 

 has not only added largely to the number of 

 species made known, but has enabled him to bring 

 together and describe man}' of the post-embryonal 

 stages of several of the forms. Twenty -eight 

 species representing eight genera of the family 

 are described, and twenty-three of the species 

 and four of the genera are new. The entire 

 anatomy of several species is worked out, and 

 the articular appendages of nearly all of them 

 are figured in detail. Under the genus Euphau- 

 sia, the peculiar eye-like organs situated on or 

 between the bases of the legs are very carefully 

 described, and apparently well shown to be lumi- 

 nous, and not visual organs. Although many of 

 the species of the family are often taken in the 

 greatest abundance, egg-bearing females are only 

 very rarely seen ; and, until very recently, noth- 

 ing was positively known in regard to the manner 

 of carrying the eggs, a single long-ago-recorded 

 observation of Bell being somewhat doubtful. 

 Professor Sars, however, has now found species 

 of several different genera, carrying masses of 

 eggs beneath the body in the same position as in 

 other Schizopoda, though not enclosed in a pouch 

 formed of lamelliform appendages, thus confirm- 

 ing Bell's observations and those of the present 

 writer, published in 1884. 



In the chapter on the development of the 

 Euphausiidae, post-embryonal stages of species 

 of Nyctiphanes, Euphausia, Thysanopoda. and 

 Nematosceles, are carefully made out, and fully 

 described and figured ; and this is all accom- 

 plished with what is usually regarded as the ref- 

 use from the surface-collecting net. These in- 

 vestigations fully confirm the observations of 

 Claus, Sars himself, Metschnikoff, and the present 

 writer, and show that the typical Euphausiidae 

 are hatched, like barnacles and copepods, as true 

 nauplii, with unsegmented body, no compound 

 eyes, and only three pairs of appendages, and 

 that they pass through a long series of inter- 

 mediate stages to the adult condition. Sars re- 

 gards this nauplial development as characteristic 

 of all the Euphausiidae. which seems somewhat 

 doubtful when we consider the small number and 



