1910.] BRITISH SPECIES OF OSTRACODA. 205 



caudal rami (fig. 10) have two nearly equal terminal claws and a 

 minute marginal seta attached a little beyond the middle of the 

 limb. 



I took a single specimen of C. fragilis in a roadside pool near 

 Carrick, Co. Donegal, and I am indebted to Dr. Thomas Scott for 

 others taken by him in Scottish lochs — L. Arklet, L. Doon and 

 Forfar loch ; but in none of these cases have I found the 

 contained animal in good condition and cannot therefore give 

 complete illustrations of it ; females only have been observed in 

 this country. 



I did not observe in any of the imperfectly preserved British 

 specimens, the conspicuous processes of the female genital plates, 

 the figure of which (fig. 10) was drawn from a specimen kindly 

 sent to me by Dr. Vavra. 



In two of Dr. Scott's specimens I found parasitic organisms 

 which appear to be the scolices of some kind of Taenia : one of 

 these is shown in PI. XXII. figs. 13, 14. The two specimens in 

 which the scolices were found are from different lakes — Loch Arklet 

 and one or other of the two further lakes referred to a,bove, so 

 that it may be fairly inferred that this particular species acts as 

 intermediate host for the Taenia. In the ' Cambridge Natural 

 History,' vol. ii. p. 84, several Ostracoda and Copepoda are men- 

 tioned as the intermediate hosts of Cestode Worms which attain 

 their final development in the intestines of Birds (Anatidse), the 

 larval forms belonging to the genus Cercoeystis. And Professor 

 R. Blanchard has described in the ' Memoires de la Societe 

 Zoologique de France ' (1891) a new genus of these worms found 

 in the same group of birds, the scolex of which occurred in an 

 Ostracod (" Gypris cinerea " Brady). This species Professor 

 Blanchard calls Echinocotyle rosseteri, and it may possibly be 

 identical with that here referred to*. In E. rosseteri, however, 

 the crown of hooks is stated to be composed of ten spines, whereas 

 in the scolices found in Candona fragilis there are, so far as I can 

 make out, tivelve. 



Candona fabceformis Fischer. (Plate XXIV. figs. 11-15.) 



1851. Cypris fabaformis Fischer, (9) p. 146, pi. iii. figs. 6-16. 

 1870. Candona diaphana Brady & Robertson, (8) p. 18, pi. v. 



figs. 1-3. 

 1889. Candona fabaformis Brady & Xorman, (2) p. 103, pi. ix. 



figs. 1-4. 

 1900. Candona fabceformis G. W. Miiller, (5) p. 29, pi. vii. 



figs. 1-7, 12, 13. 



Although W, Hartwig, in a paper on the ' Candoninse of the 



Province of Brandenburg ' (1901), dissents from our identification 



of the British specimens with Fischer's G. fabceformis, I cannot 



myself see any sufficient grounds for this dissent. The figures 



* Since these lines were in print I Lave received from Professor R. Blanchard 

 a note in which, after kindly examining- my mountings, he refers these larvse to 

 Drejoanidotcenia anatina Krahbe. 



