NO. 1573. PARASITIC COPEPODS— WILSON. 367 



In 1865 Heller described a male which he referred to this species, 

 giving the following diagnosis: 



Cephalothorax half the length of the animal, of about the same length and width, 

 posterior lobes elongate, with a border around the inner margin. 



Frontal plates wide, with a sinus at the center of the frontal margin. Second 

 abdominal segment winged on either side, wings truncated posteriorly, with a thin' 

 border on the inner side. 



All the abdominal feet biramose, rami of the first and fourth pairs two-jointed, 

 exopod of the second and third pairs three-jointed, endopod two-jointed. Genital 

 segment almost quadrate, with rounded angles. Tail one-half shorter than the 

 genital segment, two-jointed, second joint the longer, appendages elongate. Length 

 of body 7 mm. 



This shows plainly that the coi:>epod is a male of the genus 

 Echthrogaleus , and as it was found, according to Heller, in company 

 with females of Dana's species, and as its anatomy agrees with that 

 species, there is no reason to doubt its identity. 



We are thus warranted in leaving the species as Dana and Heller 

 published it, awaiting further evidence. 



ECHTHROGALEUS COLEOPTRATUS Guerin. 

 Plate XIX. 



Dinematura coleoptrata Guerin, 1837, pi. xxxv, fig. 6. 



Dinematura alata Guerin, 1837, pi. xxxv, fig. 7. 



Pandarus alatus (Milne Edwards) Johnston, 1835, p. 202, two text figures. 



Echthrogaleus coleoptratits Steenstrup and Lutken, 1861, p. 380, pi. viii, fig. 15. 



Female. — Body elongate, length more than twice the width; cara- 

 pace orbicular, as wide as long, including the posterior lol^es; lateral 

 and frontal margins strongly convex, posterior margin slightly con- 

 vex; posterior lobes long and narrow and curved inward at the tips, 

 not reaching the anterior margin of the dorsal plates on the fourth 

 segment by quite a distance. Lateral areas very narrow, the trans- 

 verse suture at about their center; the transverse suture of the median 

 area far forward and not straight, but zigzag. 



Second thorax segment distinctly separated from the third with 

 lateral plates like the lateral lobes in the male extending outward and 

 backward, but not concealed by the carapace. 



Second dorsal plates median and rudimentary, relatively wider 

 than in denticulatus; the broad apron of the third legs visible at the 

 sides of these plates in the space between the posterior lobes of the 

 carapace and the fourth segment. Third dorsal plates much enlarged, 

 trapezoidal in shape and covering a little less than half the genital 

 segment. They fit very snugly to the genital segment and project 

 only their own thickness beyond the lateral margins of the latter. 

 They just meet on the mid line without overlapping, and their entire 

 marghi is free from teeth or spines. Their chief characteristic, and 

 one which will distinguish the present species from all others, is the 



