[561] INVERTEBRATE ANIMALS OF VINEYARD SOUND, ETC. 267 
pair. The ultimate pair very long and armed with fascicles of spines 
along the margins. Divisions of the telson slender, spinous at the tips: 
In life dark greenish slate-color, changing in alcohol to dark slate. 
Length, 7-9"™. 
New Jersey to Cape Cod. 
AMPELISCA. Plate IV, fig.17. (pp. 431, 507.) 
The species’ of this genus found upon our coast have not yet been 
carefully studied. At least two species were taken in Vineyard Sound 
and Buzzard’s Bay. The genus is readily recognized, but the species 
are difficult to distinguish. 
BYBLIS SERRATA Smith, sp. nov. (p. 501.) 
Female: Dorsum rounded above, with no trace of a longitudinal carina 
upon the abdomen; third segment of the abdomen broadly rounded at 
the postero-lateral angle. Antennula about as long as the peduncle of 
the antenna; fourth segment of the peduncle of the antenna longer than 
the fifth. Inferior margins of the epimera of the first and second pairs of 
legs serrate, with slender and acute teeth alternating with the marginal 
cilia; carpus in the first pair scarcely if any longer than the propodus, 
carpus in the second pair very much longer than the propodus. In the 
third and fourth pairs of legs the dactylus as longas the propodus. Basal 
segment in the seventh pair of legs expanding distally, the posterior 
margin nearly straight, the anterior and inferior margins evenly arcuated, 
and reaching as far as the distal end of the carpus; carpus about as long 
as the ischium and merus together, a little less than twice as long as 
‘ broad, and armed with long spines upon the anterior and distal margins, 
but the posterior margin wholly unarmed; propodus almost as long as 
the carpus, and nearly four times as long as broad, anterior margin un- 
armed, the posterior armed upon the outside with two transverse rows 
of three or four spines, decreasing in size as they recede from the mar- 
gin, the distal end with a spine each side the slender dactylus. Rami 
of the first pair of caudal stylets equal, as long as the base; outer rami 
of the second pair shorter than the inner; rami of the posterior pair 
equal, longer than the bases, reaching to the tips of the rami of the first 
pair. Telson as long as the breadth at base, cleft rather more than half 
its length, the lateral margins arcuate, and rapidly converging toward 
the evenly rounded extremity. 
Alcoholic specimens are pale yellowish, the epimera, bases of the pos. 
terior legs, and the sides of the abdomen specked and mottled with 
humerous points of dark pigment crowded irregularly together. 
Length, 10-12™™, 
Deep water off Vineyard Sound and Buzzard’s Bay. 
PTILOCHEIRUS PINGUIS Stimpson. (p. 431.) 
Marine Invertebrata of Grand Manan, p. 56, 1853. Protomedia pingus Bate, 
Catalogue Amphip. Crust. Brit. Mus., p. 170, Pl. 31, fig. 2, 1862. 
Common on the whole coast of New England upon muddy bottoms 
19 v 
