54 NATURAL SCIENCE. July, 



observed were brought home. Not all that were brought home have 

 yet been determined. Not all the localities most likely to be produc- 

 tive were searched with thoroughness or searched at all. Judging, 

 then, from the general results of the " Challenger " explorations, and 

 from the special result at one spot where the conditions of investiga- 

 tion were exceptionally favourable, it may be inferred that the new 

 forms discovered, though so numerous, were few in comparison with 

 those awaiting discovery. The inference is supported by the great 

 number of species of Crustacea which have been brought to light 

 by subsequent researches, in some cases avowedly or evidently 

 instigated by the successes, or the equally suggestive failures, of the 

 " Challenger " work. 



In regard to the distribution, horizontal and bathymetrical, of 

 Crustacea, not only were a large number of facts ascertained, but the 

 problems demanding solution were brought into prominence, so that 

 subsequent expeditions have known both what points needed special 

 attention, and how they needed to be approached. 



In regard to the Brachyura, Miers believes the depth of 1,875 

 fathoms, at which Ethnsa [Ethusina) challengevi was taken, to be the 

 greatest that had been recorded for any species of crab, and points 

 out the coincidence that this genus, which supplies the deepest living 

 species of the Brachyura, is also that of which the species "evince the 

 greatest degree of degradation from the Brachyuran type." Accord- 

 ing to Dr. Henderson, any knowledge of the bathymetrical distribu- 

 tion of the Anomura was almost entirely wanting until furnished by 

 the " Challenger." His Tylaspis anomala (PI. xiii.. Fig. i) was taken at 

 a depth of 2,375 fathoms. His genus Latreillopsis is an important link 

 between Homola and Latveillia, corroborating the view that those 

 genera, at one time widely separated, and very different in general 

 appearance, ought to stand in the same family. About 2,000 speci- 

 mens of Macrura were examined by Spence Bate, including many 

 strange larval forms, as well as many fine and many remarkable 

 adult species. Some members of this series came from below 3,000 

 fathoms. The next group was claimed by Spence Bate as belonging 

 to the Macrura. It was, however, separately reported on by 

 Professor G. O. Sars, who writes : — " The collection of Schizopoda 

 procured during the long voyage of H.M.S. " Challenger " 

 has turned out extremely rich and of very special interest, 

 containing, as it does, several most remarkable new types, 

 the examination of which has led to a much fuller com- 

 prehension of the morphology of the Schizopoda and their relation to 

 other Crustacea than was previously possessed. The various 

 collections, having been made in widely-distant tracts of the ocean, 

 an important contribution to the geographical distribution of species 

 has likewise been acquired." Of the Squillidae, though the number of 

 adult specimens was small, the collection, according to Professor 

 Brooks, " throws light upon many interesting problems, and furnishes 



