IDOTEA APPENDICULATA. 397 
upper antennz have the basal joint short, but very much 
dilated ; the basal joint of the outer antennz is not 
visible from above ; the four following joints are mode- 
rately robust and nearly equal in length; the flagellum 
is long, slender, and multiarticulate. The eyes are placed 
in the middle of each side of the head, the anterior- 
lateral angles of which are strongly produced and 
rounded. The legs are slender and attached close to and 
beneath the lateral angles of each of the segments of 
the body. 
The tail is considerably elongated, being about one- 
third of the length of the entire animal; it is lanceolate 
in form, being more or less suddenly dilated at a short 
distance beyond the middle. It appears to consist of 
only a single segment, but faint traces of articulations 
can be seen at each side near the base. 
Besides Dr. Leach’s Sidmouth specimen, which is 
labelled I. lancifer, the British Museum possesses speci- 
mens from Ilfracombe, collected by Mr. Gosse, and we 
have received it from Polperro from Mr. Loughrin. 
The species is also given in the List of Jsopoda in the 
Reports of the British.Association for 1860, p. 225. 
