2,38 ON THE BRITISH SPECIES OP EliTTOMOSTRACA 



The only British locality in which Daphnia Jardinii hsis 

 hitherto been found is Lochmaben, Dumfriesshire, where it 

 occurs in several of the lakes. It was first found there by Dr. 

 Baird, and has more recently been taken abundantly by Dr. 

 Norman and myself. Together with another interesting Ento- 

 mostracan — Bosmima Coregoni — it seems, as was pointed out by 

 Dr. Baird, to constitute a principal part of the diet of the Vendace 

 -^a fish peculiar to Lochmaben and said to have been introduced 

 there by the Eomans. 



Hyalodaphnla Kahlbergensis (Schoedler), (PI. IX., figs. 



18-20; pi. X,, figs. 16, 17}. 



1864. Daphnia Kahlbergensis^ Schoedler, Die Cladoceren des 



frischen Haffs (Archiv f. Naturgeschichte XXXII., 



Jahrg I. Bd.), p. 18, pi. I., figs. 1-3. 



Female. — Seen from the side the shell is elongated, the greatest 

 height situated behind the middle, and equal to about one-third 

 or one-half of the length. Head narrower than the body, and 

 occupying from one-third to one-half of its length, widest at 

 the posterior or rostral end, tapering evenly to the front, and 

 there produced into a more or less acute median spine, which 

 points directly forward or may have a slightly dorsal bend; 

 ventral margin of the head sinuous and more or less prominent 

 in the middle, ending in a subacute, prominent beak. Dorsal 

 margin of the shell almost straight in front over the head, then 

 gently curved to the hinder extremity, but with a slight depres- 

 sion near the middle ; ventral margin boldly arched, ending in 

 a long spine which springs from near the dorsal angle and is 

 directed backwards and slightly upwards; the spine, together 

 with the posterior shell margin, is fringed with sharp spinules. 

 Dorsal processes of abdomen (plate X., fig. 17) extremely small; 

 pre-anal spines ten to twelve in number and progressively larger 

 -from before backwards; terminal unguis long, slender, and with- 

 out serratures on its convex side, but having its concavity fringed 

 -with a series of very delicate, closely-set hair-like cilia. Length, 

 ■2'1 mm. 



