75 
2. Telson acute, triangular. C. acutum Chewr.^) 
— not acute at the apex.C. lacustre Vanhotfen.^) 
3. Ocular lobes acute triangular (J' has rostrum short; ? has 
penultimate joint of peduncle in ant. 2 more than twice as 
broad as ultimate joint).C. crassicorne Bruzel. 
Ocular lobes ovate with rounded apex. 4. 
4. ?. 5- 
^ .see the list above 
(p. 74; C. acherusicum and C. Bonelli). 
5. Underside of A. peduncular joint of ant. 2 has one spine. 
C. Bonelli. 
_ . — — — - two spines. 
C. acherusicum. 
Corophium Bonelli (M.-Edw. ?) G. O. Sars. 
5 agrees totally with G. O. Sars 1895, p. 617, PI. 221, fig. 1, 
except in the following character: front (fig.3, ? ) produced in a broad 
triangle (as noted by Stebbing 1906, p. 691), cannot be character- 
ized as being “without any rostrum“ (as noted by Sars 1. c.). — 
Total length (? with ova) as a rule only abt. 4 mm, not 6 mm. 
cT was totally unknown till it was described from Alaska by 
Shoemaker 1920, p. 22. Upon the whole my specimens agree very 
well with Shoemaker’s description, but they differ in the following 
points. — Ant. 1 : Only in a very few cases I have been able to find 
the apical spine on 1. joint of the peduncle, and I have never found 
the central spine on the said point. On the median edge of the 
underside of the same joint there is a process not mentioned by 
Shoemaker (see the list above p. 74; fig. 3, cT). Flagellum has 9 (not 
7) joints. — Ant. 2: the strong apical tooth of 4. joint in peduncle 
varies in length (see fig. 3); sometimes there is not one, but two 
additional teeth. 
1) C.acutum: Chevreux, Buil. Soc. Zool. France, vol. 33, no. 3—4, 1908, 
p. 75, figs. ( 5 ) (loc.: Bona, Algérie). 
2) C. lacustre: Vanhoffen, Sitzungsber. Gesellsch. Naturf. Freunde, Berlin, 
1911, p. 400, figs. (J', (brackish water in the Frische Haff, among 
floating freshwater plants). — C. 1: Sexton, Proc. Zool. Soc. London 1912, 
p. 664, figs. (brackish water; Bremerhafen, Frische Haff). — C./.: Hel- 
lén, Soc. Fauna et Flora Fennica, Meddel, vol. 45, 1919, p. 136 (Borgå in 
Finland, 2—4 m, salinity 3,60—4,58 %o)- 
