246 Transactions.—Zoology, 
Group ABERRANTIA. 
Coxe of the pereiopoda not squamiformly developed, some, or all, 
being fused to their respective segments. One or more segments of the 
pleon absent. 
Fam. Caprellide. 
Pleon rudimentary. Oral appendages normally developed. Cox fused 
with the pereion. Branchial sacs attached to the first two or three 
segments of the pereion. 
Genus I, Caprella, Lamarck, Syst. des. Anim. sans Vert., p. 165; 
Edwards, Hist. Nat. Crust., iii., p. 105; Spence Bate, Brit. Mus. 
Cat. Amphip. Crust., p. 353. 
Body cylindrical. Cephalon and first segment of the pereion confluent. 
Pleon rudimentary. Gnathopoda subchelate. First two pairs of pereiopoda 
represented by the branchis attached to their respective segments only ; 
three posterior pairs of pereiopoda subequal. First and second pairs of 
pleopoda rudimentary in the male ; the rest obsolete. 
21. Caprella caudata, nov. sp. Fig. D.5. 
Female. Body rather robust. Cephalon smooth, not toothed nor 
tuberculate, short; four succeeding segments of pereion subequal. Eyes 
round. Superior antenne more than half as long as body; first joint of 
peduncle with an acute spine on the antero-superior margin; second joint 
longest; flagellum about 15-jointed (first few fused together), as long as 
peduncle, and spinose at the articulations. Inferior antenne more than 
half as long as the superior; two basal joints short and smooth; the rest 
fringed on their lower margin with long hairs. Maxillipeds well developed, 
unguiculate, ciliate on the lower margin, with the carpus distended. First 
pair of gnathopoda small and fringed with hairs; carpus with a deep 
transverse incision; propodos ovate, dactylos long and slender. Second 
pair of gnathopoda large; propodos narrow-ovate, with the palm extend- 
ing along the greater part of the lower margin, with a large tooth 
surmounted by two spines to receive the point of the dactylos, and two 
smaller teeth nearer the hinge corresponding to two indentations in the 
dactylos; dactylos stout, curved. Branchie narrow-oblong. Ovigerous 
pouches nearly circular, thickly ciliated on their inner margins. Three last 
pairs of pereiopoda increasing in size posteriorly, similar in shape; in all 
the propodos is narrow, excavate along its anterior margin to receive the 
slender curved dactylos, point of impingement of which is marked by two 
serrated spines. First pair of pleopoda rudimentary, represented by minute 
tubercles. Pleon prolonged into a slender flat expansion. 
Dunedin, in rock pools. Length -4 inch, 
