148 
HISTORY or BRITISH CRUSTACEA. 
late Henry Goodsir, who named it after the Rev. Dr. 
Pleming, Professor of Natural History in New College, 
Edinburgh. He found it in shallow water. 
A species of the genus Thysanopoda has been found in 
Britain — the T. Couchii : the gills in this are in the form 
of plumes at the base of the feet ; the last pair of feet are 
unbranched. The type of the genus was found in the At- 
lantic Ocean. Professor Bell thus characterizes the 
Thysanopoda couchii, Bell. — Branchiae with only one 
series of leaflets. Middle point of the trifid apex of the 
central caudal lamina not half the length of the lateral 
ones. 
Cornish coast (Mr. Couch) ; found in the stomach of a 
mackerel. 
Pam. JDIA STYL ID2E, Spence Bate. 
Gen. 51. DIASTYLIS, Say. 
Carapace produced in front as a beak. Eyes confluent t 
on the top. Pive segments of thorax exposed behind cara- 
pace. Upper antenna short, scarcely reaching to the fore 
margin of carapace. Lower antenna longer than the 
upper. Pirst five abdominal segments without appendages, 
