24 



PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxiv. 



LEIDYA DISTORTA (Leidy). 



Cepon distortus Leidy, Jour. Acad. Nat. Sci. Phila., (2), III, 1855, p. 150, 

 pi. xi, figs. 26-32.— Harger, Report U. S. Fish Commission, Pt. 6, 1880, 

 p. 311. — Kossmann, Zool. Ergeb. einer Reise in die Kiist. des Rothen 

 Meeres, III, Malacostraca, 1880, p. 122 ; Mittheil. aus der Zool. Station 

 zu Neapel, III, 1881, first half, p. 182.— Richardson, Am. Nat., XXXIV, 



1900, p. 309. 



Leidy a distorta Corn alia and Panceri, Mem. R. Acad. Sci. Torino, (2), 

 XIX, 1858-1861, p. 114. — Giard and Bonnier, Trav. du Labor, de Wime- 

 reux, V, 1887, p. 68, fig. 12.— Richardson, Proc. U. S. Nat. Mus., XXIII, 



1901, p. 579; Bull. TL S. Nat. Mus., No. 54, 1905, pp. 511-512. 

 Localities. — Atlantic City*, New Jersey, on TJca pugilator (Bosc) ; 



Bermudas on Pachygrapsus transversus (Gibbes). 



It is interesting to note that although Leidya distorta was first 

 found at Atlantic City, New Jersey, its host, TJca pugilator, extends 



as far south as the coast of Florida, and 

 the new host, Pachygrapsus transversus, 

 extends as far north as the Florida coast, 

 so that the continental ranges of the two 

 hosts overlap. 



Description of female. — Body rather ir- 

 regular in outline, oblong-oval. Cojor 

 yellow. (See figs. 1-2.) 



Head large, bilobed, and with the front 

 produced in a wide border or margin. 

 Eyes wanting. 



fig. ia. — Leidya distobta. adult First two segments of thorax short. The 

 female (dorsal view). three following segments are the largest, 

 and are subequal in length, about twice as long as the first; sixth a 

 little shorter than fifth ; seventh about half 

 as long as sixth. The second, third, fourth, 

 and fifth segments have in the middle of 

 the dorsal part of the segment a squarish 

 plate, which in the fifth segment has the 

 outer edges considerably elevated, so as to 

 form a longitudinal carina on either side, 

 which extends posteriorly over the sixth 

 segment. Coxal plates or epimera are pres- 

 ent on the anterior portion of the lateral 

 margin of all the segments, but are almost 

 completely hidden by the large ovarian 

 boss which projects upward in a large, 

 prominent lobe. There are five pairs of incubatory plates, which 



Fig. 2.— Leidya distorta. Adult 

 female (ventral view). 



a Figs. 1, 2, and 5 are from photographs taken in the U. S. National Museum. 

 In the specimens photographed the pleural lamellae and the pleopoda were 

 bent, so that they do not appear as long as in Leidy's figures. 



