1895. RESULTS OF "CHALLENGER'' EXPEDITION. 55 



the material for a more exhaustive and satisfactory discussion of the 

 phylogenetic relationsliips and the natural classification of the various 

 genera and species than has been possible hitherto," Further he 

 remarks that " the collection of pelagic Stomatopod larvae is very rich, 

 and it has yielded the material for tracing the history of several of the 

 larval types, and also for establishing, in every genus except one, the 

 connection between the adults and their larval types." Of the 

 Cumacea only fifteen species were obtained, but fourteen of them 

 were new. Members of this group can descend to a depth of 2,000 

 fathoms. At a like depth were found nine species belonging to seven 

 distinct genera of Isopoda. In the Amphipoda the wide range of the 

 Hyperidae was decisively made patent, these being especially pelagic 

 animals, most of them probably passing a great part of their time at 

 or near the surface, while those which descend to great depths seem 

 capable of coming af least occasionally to the top of the water. Among 

 the Gammaridae, also, there are some wide-ranging species, since some 

 are common, for example, to Kerguelen and Great Britain; but, how- 

 ever cosmopolitan some forms may be, every new locality explored 

 seems to reveal some gammarids of its own. The " Challenger " 

 collection of Amphipoda has helped to show that, notwithstanding the 

 many striking differences among them (PI. xii., Figs. 3, 4), they are 

 at present an order as clearly and sharpl}^ defined as any in the animal- 

 kingdom. All the known species in zoology are either decidedly 

 amphipods or decidedly not amphipods. Time and space, however, 

 are not so poor but what the intermediate forms, alive or dead, may 

 yet be discovered. In contrast to the Amphipoda, which at present 

 are practically unknown to geology, the Phyllocarida have long been 

 limited to palaeozoic fossils, with the small exception of the living 

 Nebalia bipes. But the " Challenger " Expedition tripled the extant 

 contents of the group by adding two new species and two new genera. 

 Metschnikoff considered Nebalia to be a " phyllopodiform decapod," but 

 Sars, after a detailed consideration of the forms at his command, 

 believes that its relationship to other crustaceans will be more 

 correctly expressed by calling it " a copepodiform branchiopod." As 

 for the Copepoda, Dr. John Murray says that they were rarely, if 

 ever, absent from the tow-net gatherings when examined on board 

 ship. That ah these gatherings did not come into Dr. Brady's hands 

 is easy to explain. As every collector knows, the most ardent desire 

 for storing specimens is sometimes quenched by the prolific 

 abundance, the obtrusive superabundance, of aquatic life. Little 

 account is made of Crustacea by landsmen because they are so 

 seldom in view. Insects are rare in the ocean. But what insects 

 are on land, that crustaceans are at sea — sometimes remorselessly 

 plentiful. Thomas R. R. Stebbing. 



The above general summary of the results in Crustacea pays 

 regard to the fact that we have been favoured with special notes by 



