190 LIVERPOOL BIOLOGICAL SOCIETY. 
large numbers by Mr. Sinel at Jersey. Still later, isolated 
specimens of C. herdmani and C. rigidum have been found 
in tow-nettings taken both in the Firth of Clyde and the 
Firth of Forth. Both species appear to be widely distri- 
buted, but rarely plentiful. 
Family. LERN@IDA. 
Lernea branchialis, Linn. (Pl. VIIL., figs. 1—6). 
About a year ago two very minute Crustacea (fig. 1) were 
taken in the tow-net off Puffin Island, which appeared 
to be larval forms of a Lernea. Since then two adult 
specimens (one from the same locality) have been found, 
apparently belonging to the same species as the larval 
specimens. They agree in the main with Lernea bran- 
chialis, Linn., described and figured by Claus in his 
‘“‘ Beobachtungen ueber Lerneocera, Peniculus und Lernea, 
1868.” The adult forms correspond in most particulars 
with the male and female described by Claus, and I have 
provisionally included them under this species. Our 
specimens differ from those figured by Claus chiefly in 
the form of the prehensile posterior antenne and in the 
segmentation of the abdomen; but as will be seen (PI. 
VIIL., figs. 1, 5 and 6), this animal appears to vary much 
in these very particulars according to age and sex, and it is 
therefore quite likely that Claus’s specimens may repre- 
sent slightly other stages of development. ‘The group is 
extremely interesting, as exhibiting progressive and retro- 
gressive development, and deserves more attention than it 
appears to have hitherto received. The female (fig. 6) is 
about 1-18th inch in length, the male rather smaller, and 
the larval form (fig. 1) about half the size of the female. 
I am indebted to our colleague Mr. Helenus Robertson 
for kindly producing enlarged micro-photographs of this 
“ osha heard 
