264 NATURAL SCIENCE. April, 



elongate hand, and this filiform hand is attached to the apex of a 

 wrist which is little stouter than itself though much exceeding it in 

 length, an eccentric formation, about as remote from the ordinary 

 type as any that is known. A definition which smothers up every 

 hint of such a disparity, in the expression " gnathopods subchelate," 

 rather confuses knowledge than clears its flow. 



But, to leave the " Challenger " genera, in regard to which I 

 may be suspected of fighting for my own hand, it will be worth 

 observing that, just when Delia Valle is making Amphithopsis nodifera 

 of Sars into a species of the omnivorous Acanthozone, Sars himself is 

 coining for it his new genus Stenoplenstes. Nor is this the only new 

 genus established by Sars over which the car of Juggernaut has 

 rolled. For though his Leptamphopus and Haliragoides were published 

 too late to be noticed in the Italian work, they were absorbed in 

 Acanthozone by anticipation, slain, as it were, before they were born. 

 Four other genera also, not mentioned in the generic synonymy, in 

 whole or in part, lie crushed beneath the same destroying wheels. 

 And yet, after all, if the precedents of history may be trusted, a 

 resurrection awaits them. In vain, for instance, did Herbst ignore 

 the genera established by Fabricius. For presently Leach arose to 

 reinstate them and add largely to their number. In vain did Sabine 

 in 1821 sigh over the multiplication of genera, and fancy that in con- 

 ceding two to the Gammaridea he was conceding one too many. In 

 vain, a little later, did Milne Edwards suppress the Melita and Mcera 

 of Leach, for these are accepted even by Delia Valle. In vain did 

 Kroyer scoff at Owen's Acanthosoma as "a structure built upon the 

 sand," for, as I have shown, it is this very genus that Delia Valle has 

 exalted to that sort of giddy height where absolute dominion can 

 tolerate no brother near its throne. 



In turning to the specific synonymy within this masterful genus, 

 one discovers over and over again that species which Delia Valle 

 unites under a single specific name are considered by Sars to belong 

 actually to different genera, even in one case to different families. A 

 species described by Hansen and Vosseler from the Arctic regions is 

 identified with another described by G. M. Thomson from New 

 Zealand. So great a range of distribution is not unexampled, but it 

 is far from common. Difference of habitat, however, counts for 

 nothing, if the descriptions of the specimens agree. In this par- 

 ticular instance they happen to differ. The Italian professor does 

 not take upon himself to say, " so much the worse for the descrip- 

 tions," but he makes use of a formula almost as elastic in declaring 

 that this, that, or the other portion of an organism is variable. The 

 wonder is that with such a formula he can bring himself to admit 

 any distinctive names at all. 



The student will, perhaps, expect that the genus just discussed 

 will be separated from that which follows it by some grand and 

 striking features. He will find, on comparing the two definitions, 



