356 PROCEEDINGS OF THE NATIONAL MUSEUM vol. loi 



as wide as long, with rounded lateral angles, wider in front than 

 behind. Abdomen 2-segmented ; first segment three times as long 

 as wide ; second segment one-fourth as long as first. Caudal rami 

 slender, tapering, twice as long as genital segment; tipped with 

 three short setae. 



Measurements : Length, 3 mm. 



Male. — Front of head straight, without lobes. Cephalothorax 

 slightly wider and shorter than remainder of body, from which 

 it is sharply separated laterally by incisions ; covered dorsally by 

 an elliptical plate. Second to fourth thoracic segments wider than 

 genital segment, which is about as long as the remainder of the 

 thorax. Anal papillae setose, as are the caudal rami distally. 



First antenna 6-segmented ; at front of head. Second antennae 

 larger than those of female; terminal hook curved, spinulose at 

 tip. Mouth tube long and slender. First maxilla with a long basal 

 seta and 2 terminal setae. Second maxilla with spinulose terminal 

 hook. Maxilliped slender, not much larger than second maxilla. 



First legs spinulose on basipod ; exopod with five terminal 

 spines ; endopod setose on median border, with one terminal spine. 

 Second legs with exopod ending in a circular spinose disc ; the basi- 

 pod and endopod setose medially, the latter with a single terminal 

 spine. Third and fourth legs flat, uniramous, leaflike, with pointed 

 tips; the fourth about twice as long as the third, extending far 

 beyond the caudal rami, which are slender, one-fourth as long as 

 the fourth legs, and tipped with a single seta. 



Measurements : Length, 2.2 mm. 



Tijpes.— Female, U.S.N.M. No. 88555 ; male, U.S.N.M. No. 88556. 



Hosts. — Three females and one male taken from the gills of 

 sheepshead, Archosargus probatocephalus (Walbaum), and seven 

 females from the saucer-eyed porgy, Calamus calamus (Cuvier and 

 Valenciennes) . 



Remarks. — This species is like Wilson's (1922) L. clilamydotus 

 and L. penulatus in having a long dorsal plate, but it differs from 

 them in having frontal lobes in the female, in the shape of the 

 dorsal plate, and in the shape and armature of the mouth parts. 

 The frontal lobes are like those of L. caudatus, but the dorsal plate 

 is quite different from that species. It most closely resembles L. 

 pagelli Kr0yer (1863) , but it differs in the greater spinosity of the 

 mouth parts, the shape of the male and female abdomens, and 

 caudal rami. It also resembles L. pupa Burmeister (1833), but it 

 differs in the armature of the mouth parts, in the character of the 

 first maxillae, the armature of the exopod of the second legs, and 

 the caudal rami, and in its smaller size. 



