52 NATURAL SCIENCE. July. 



fathoms. Moreover, the genera which occur there are well known ; 

 and for this reason it is probable that further exploration will enlarge 

 the area of the new genera. Those procured from the profound 

 abysses are mainly tube-dwellers, and thus are more or less protected, 

 though at the same time this fact renders their presence in the trawl 

 or dredge more frequent. The consideration of the annelidan in- 

 habitants of the abysses of the Pacific and the Atlantic, affords no 

 countenance to the view that primitive types have been gradually 

 pressed by the more prolific and hardier shallow-water forms deeper 

 and deeper into the ocean. 



Again, the food of these deep-sea forms demonstrates that many 

 of the lower organisms, such as Foraminifera, Radiolaria, and 

 Infusoria dwell at the bottom, and are devoured in the living 

 condition, a fact which at once disposes of the view that nourishment 

 is absent there. The deepest abysses of the ocean are inhabited by 

 Annelida, and thus, food for fishes especially is to be found. More- 

 over, in regard to development, the same series of phenomena appear 

 to occur in the benthal types as in those of shallow water, and in 

 those frequenting tropical oceans as well as those amidst the 

 polar ice. 



In the Nemertea collected by the " Challenger," which I 



had glanced at before handing over to my distinguished friend, 



Professor Hubrecht, it was found that no change was required to 



be made in the classification adopted by the reporter (Professor 



Hubrecht), which, after all, by the aid of new terms, only rings 



changes on that founded on anatomical features, and clearly set forth 



in the work for the Ray Society in 1873. The latter classification 



remains as satisfactory now as formerly, though, it is true, its quiet 



terms do not appeal to theory. Amongst the striking discoveries in 



this group — made by the lamented Moseley — is Pelagonemertes (PI. xii., 



Fig. i), a pelagic form, figured as a mollusc by former travellers, which 



falls under the sub-order Anopla and the family Amphiporidae, even its 



branched alimentary canal being similar to that of N emeries gracilis. 



Two important new genera were also discovered, viz., Carinina and 



Eupolia, the latter placed under a special family. This valuable 



collection enabled Professor Hubrecht to enrich his report by an 



elaborate anatomical appendix, in which the additions to our 



knowledge were incorporated with the leading features already 



ascertained. 



W. C. McIntosh. 



Arthropoda. 



In the zoology of the " Challenger " the reports on Crustacea 

 occupy between a fourth and a fifth part of the text, and more than a 

 fourth part of the 2,536 plates by which that text is illustrated. They 

 describe nearly a thousand new species, besides throwing a fresh light 

 upon a multitude of old ones. That carcinology should have claimed 

 so predominating a share in the " Challenger " record is, for more 



