Amphipoda with notes on a species of Isopoda. 
449 
It is as well, perhaps, to indicate the relationship of the new species here 
described by reference to Stebbing's key and for that purpose I give below a list of 
all the species of Gammarus not included in that key with an indication of their 
approximate position as far as can be judged from the published description. 
Species. 
G. caecus, vVeckel, 1907. 
G. haasei, Sayce, 1902. 
G. tetrachantus, Garbini, 1902. 
G. capensis, Barnard, 1916. 
G. nigroculus, Barnard, 1916. 
G. crassicornis, Barnard, 1916, 
G. auricularis, Barnard, 1916. 
G. harringtonensis, Chilton, 1916. 
G. australis, Sayce, 1 901. 
Position in Stebbing's Key. 
Distinguished at once from all other species 
by the absence of eyes. 
Distinguished from all the other species by 
having the last thoracic and first three 
abdominal somites produced dorsallyinto 
a median process. I should very much 
doubt if it is correctly referred to Gamma- 
rus. 
Excluded in Stebbing's key under heading 
7 and therefore allied to G. obesus, Sars. 
G. 
G. 
ramellus, Weckel, 1907. 
sowinskii, Behning, 1914. 
Excluded in Stebbing's key under heading 
13 and therefore allied to G. weidemanni, 
G. O. Sars, and G. maeoticus, Sowinsky. 
Excluded in Stebbing's key under heading 
> 22 and therefore allied to G. pungens, 
3 M.-Ed. 
Excluded in Stebbing's key under heading 
24 and therefore allied to G. duebenii, 
Excluded in Stebbing's key under heading 
26 and therefore allied to G. pulex, Linn. 
■\ Excluded in Stebbing's key under heading 
C 29 and therefore allied to G. locusta, 
) Linn. 
Owing to deficiencies in the published descriptions and figures I am unable to 
place the following species in their proper place in vStebbing's key 
G. sarsii, Sowinsky, 1898. 
G. vipensis, G. Smith, 1909. 
G. antipodeus, G. Smith, 1909. 
G. breweri, Kunkel, 1910. 
G. purpurascens, W. P. Hay, 1902. 
G. propinquus, \V. P. Hay, 1902. 
Of these six species, the first three have the inner ramus of the third uropods 
very short and are comparable in this respect to G. annandalei. But the descrip- 
G. chevreuxi, Sexton, 1913. 
G. limnaeus, S. I. vSmith, 1874. 
G. zaddachi, Sexton, 1912. 
G. pribilofensis, Pearse, 1913. 
