686 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. 55. 



The head is a narrow lobe at the anterior end of the cephalothorax, 

 less than half the width of the latter, and somewhat three-cornered 

 in both dorsal and ventral views, widest along the anterior margin 

 and narrowing to a rounded point posteriorly. From the center of 

 the anterior margin project the second antennae, which are rather 

 small transverse ellipsoids. Between these and the dorsal surface of 

 the head, and entirely concealed by them, are the small knobs repre- 

 senting the first antennae. 



On the ventral surface of the head, a short distance behind the 

 bases of the antennae, is the month opening. On either side of this 

 and some distance from it are the first maxillae, and behind the 

 opening are the second maxillae, close together on the midline. On 

 either side of the head is a large pad-like process, curved both dor- 

 sally and ventrally, and ending in bluntly rounded points, those of 

 the two processes not quite meeting on the dorsal and ventral surfaces. 



Color (preserved material), a yellow- white ; the neck and trunk 

 with a brownish tint, the egg strings a deep orange. 



Total length, including the posterior processes, 55 mm. Cephalo- 

 thorax, 15 mm. long, 1-1.50 mm. in width. Neck, 15 mm. long, 

 0.50 mm. wide anteriorly, 1 mm. wide posteriorly. Trunk, 15 mm. 

 long, 12 mm. wide, 8 mm. thick. Posterior processes 10 mm. long. 

 Egg strings 42 mm. long, 2 mm. wide. 



(gracilis slender.) 



Remarks. — The distinguishing characters of this species are the 

 narrow and elongated cephalothorax, neck, and egg strings, the tiny 

 three-cornered head, the twisting of the neck and its armature of 

 small, irregular knobs, and the large and plump trunk. The two 

 hosts upon which it was found are closely related fishes of the deeper 

 portions of the Atlantic. 



REBELULA EDWARDSII (Kolliker). 



Lophoura edwardsii Koixiker, Zeit. fiir wiss. Zool., vol. 4, 1853, p. 299. 

 Lophoura edwardsii Cornalia, Atti del soc. Italiana di Sci. Nat., vol, 9, 

 1865, p. 1. 



Host and record of specimens. — Kolliker's specimens were secured 

 at Messina from the body of a Lepidolepms caelorhynchus, while 

 Cornalia's were taken from the same host at Naples. The latter 

 were fastened in the flesh above the vertebral column, the head pass- 

 ing in between the spinous apophyses of the vertebrae to the dorsal 

 aorta. 



SpecifiG characters of female. — The following account is adapted 

 from Cornalia, who has given us the best description of the species. 

 The anterior part of the body is made up of a soft cylinder, about 

 1 mm. in diameter, with a roughened skin. The extreme tip of the 

 cylinder may be regarded as the true head, and it is separated from 



