[ 395 ] 

 AUG 29 i«9^ 



VIII. Amphipoda, from the CopenJiagcJi Muscjnn and other Sources. — Part II. 

 By the Heo. Thomas R. R. Stebbing, M.A., F.B.S., F.L.S. 



(Plates 30-35.) 



Read 3rd November, 1898. 



Introdtjctory Remarks. 



JN O panegyrist of the Amphipoda has yet been able to evoke anything like popular 

 enthusiasmi in their favour. To the generality of observers they are only not repellent 

 because the glance which falls upon them is unarrested, ignores them, is unconscious of 

 their presence. The majority of the species keep themselves effectively concealed from 

 all but pertinacious intruders, beneath stones and weeds and varying depths of water. 



Of the families to be dealt with in these pages the first is the Orchestiidae, or, as some 

 might prefer to call it from the genus fii'st described, the Talitridae. This is of all the 

 Amphipoda the family whicli has made the strongest eff'ort to place itself in evidence 

 and to overcome the disregard of a neglectful world. More than any of the tribe it has 

 invaded the land, so that its representatives may be found, not only in the sand-hillocks 

 above high-water mark, but in gardens, in woods far from the sea, on hills, in ci'aters of 

 extinct volcanoes. It has climbed higher than any of the Crustacea excejit a few wood- 

 lice, some of the freshwater forms having been taken by Mr. Whymper at a height of 

 more than thirteen thousand feet in the Gi-eat Andes. Another mark of distinction may 

 be found in the excessive trouble which nature and art have enabled it to give to the 

 systematist. Not only are the descriptions and figures bequeathed to us by eminent 

 naturalists and artists full of puzzles, but the creatures themselves have conspired in 

 various ways to make the path of knowledge thorny and fatiguing. 



Genera, the S2:»ecies of which have different habits, and which are separated by the 

 unlikeness of the males, are in the females scarcely distinguishable (Talitrus and 

 Orchestia). Genei'a which have been put apart by a decisive character provokingly 

 join hands just when their separation is most needed. A great increase in the number 

 of known species brings to light the missing links, which, as every one knows, are the 

 curse of classification [Orchestia and Talorchestia). 



Characters which at one time distinguished large groups, or were valid for the Avhole 

 family, are gradually nibbled away by exceptions here and exceptions there till all the 

 neatness and comj)leteness of the arrangement they provided are muddled away and 

 spoiled. Por example, it can no longer be stated with precision that the Orchestiidae 

 always have the first antennae shorter than the second, and the third uropods with never 

 more than a single branch. It is safer to say in the one case almost always and in the 



SECOND SERIES. — ZOOLOGY, VOL. VII. 55 



