192 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
Female: Eye-lenses close together, sometimes contiguous; fifth thoracic segment very short. 
Anterior antennae 6-jointed, similar to those of Onecea, hut with naked bristles and without aesthe- 
t-asks. Posterior antenna' with voluminous second hasal joint and very short first joint to inner 
ramus; first and second basal joints each with a long, thick bristle and inner ramus with stout, 
much-curved uncinate bristles. Terminal joint of anterior maxillipeds ending in a strong hook. 
Second basal of posterior maxillipeds with a bristle on inner margin; its end-hook more delicate than 
in Sappldrina. Outer ramus of feet longer than inner ramus; outer bristles of outer rami in first and 
second pairs have forms of denticulate lancets (1, 1, 3, more rarely 0, 0, 1) and are more or less abortive 
in succeeding pairs; inner rami of first pair with 1, 1, 5, in second with 1, 2, 4, in third with 1, 2, 2, in 
fourth with 1 or 2 bristles. 
Male: Genital valves long, each with a single bristle; pronounced deviations are shown by the 
posterior antennae and posterior maxillipeds, especially in the elongation of the terminal hook. 
29. Coryceeus elongatus Claus. 
Female: Cephalothorax with 4 segments, abdomen with 1 segment; ventral keel rounded; furca 
between three-sevenths and four-sevenths as long as remaining abdomen. Bristles of first basal joint 
29. Coryceeus elongatus Claus; female; a, dorsal 
aspect: b, lateral aspect; c, fourth foot. 
30. Coryceeus carinatus Giesbrecht; female; 
a, dorsal aspect; b, lateral aspect. 
of posterior antenna' but little longer than those of second hasal joint. Third joint of outer ramus of 
first to third foot with 3 outer marginal bristles; inner ramus of fourth foot represented by a plumose 
bristle. 
Male: Boundary between head and first thoracic segment indistinct. Abdomen with 2 segments, 
posterior portion of genital segment not tapering; furca one- third to one-half as long as remainder of 
abdomen; tooth on inner edge of second basal joint of posterior antenna? replaced by fine points. 
Coloration : Rather opaque, with a variable amount of red, yellowish-red, and yellow pigment, 
especially in region of mouth, in wing-like extensions of posterior thoracic segments, and in genital 
segment. Eye red. Eggs yellowish or reddish. 
Length of female, 1.45 to 1.05 mm. ; of male, 1.3 to 1.4 mm. 
A few females taken in tow in Gulf Stream, 70 miles south of Marthas Vineyard, July 28, 1899. 
30. Corycasus carinatus Giesbrecht. 
Female: Cephalothorax with 2 segments, abdomen with 1 segment; ventral keel beak-shaped, 
extending backward; abdomen tapering posteriorly ; furca half as long as remainder of abdomen, four 
times as long as broad. Male unknown. Coloration as in the preceding species. Length, 0.85 to 0.9 
mm. Several female specimens taken in company with preceding species in the Gulf Stream. 
