182 0. 0. SARS, 



Gammarus. In the next article, to be sliortly published, the remaining 

 species of Gammarus will be described, and in a Srd article some other 

 Gammaroid genera will be treated off, as also the rather numerous species 

 of Goroplnum occurring in the Casi)ian Sea. 



The figures are, as in my two former papers reproduced by the auto- 

 graphic methode, and particular care has been applied in making them as 

 correct and instructive as possible. 



Fam. GAMMARIDiE. 

 Gen. 1. Boeckia, Grimm (not Malm). 



Generic characteristic. — Body very robust, with greatly iucrusted in- 

 teguments, and having the metasome and urosome poorly developed. Seg- 

 ments of mesosome produced laterally to extant spiniform processes, that of 

 the 5th segment being particularly strong and nmcrouiform. Cephalou pro- 

 duced in front to a distinct rostrum, and having on each side a greatly 

 prominent spiniform projection. Anterior pairs of coxal plates rather deep; 

 4th pair but little broader than the preceding pairs, and very slightly 

 emarginated posteriorly. Eyes distinct, placed on the lateral faces of the 

 cephalou. Superior antenuse longer than the inferior and having the acces- 

 sory appendage obsolete. Oral parts normal. Gnathopoda comparatively 

 small, subchelifoi-m, and but little different; those in male somewhat stronger 

 built than in female, with the propodos broader. Pereiopoda rather 

 elongated and nearly equal in length, basal joint of last pair broader and 

 more larainai- tliaii that of the 2 preceding pairs. Branchial lamellae large, 

 subpedunculated; incubatory lamellae well developed. Uropoda very unequal 

 in size, the last pair being rather small, not nearly reaching beyond the 

 others and having the inner ramus extremely minute, scale-like, the outer 

 linear and without any terminal joint. Telson very small, unarmed, and 

 slightly cleft at the tip. 



Remarks. — The name Boeckia, it is true, has been long ago appr- 

 priated in Zoology, liaving even been proposed at different times by 2 

 different authors, viz., by Malm for a genus of Amphipoda, and by Mr. 

 Geo. Thomson for a fresh-water Copepod. But in both instances the name 

 has been withdrawn, that of Malm being synonymous with Leptocheirus of 

 Zaddach, and that of Thomson having been changed by Mrss. Guerin 

 and Richard to Boeckella. It seems to me therefore that there cannot be 

 any ol)jectiou in using this name now in a new sense, and in every case I 

 find it unreasonable that the name of such a diligent investigator as the late 

 Dr. Boeck should not be justly associated with the order of Crustacea that 



*Q3.-MaT. CTp. 182. 4 



