NO. 2063. NORTH AMERICAN PARASITIC C0PEP0D8— WILSON. 657 



Remarks. — This is the only parasite within tlie author's knowledge 

 that has ever been found upon the common dogfish along our North 

 American coasts. Doctor Lambert has handled thousands of dogfish 

 specimens for laboratory purposes, and this is the only instance in 

 which any copepods have been found upon them. The species, 

 therefore, can not be at all common; it may be readily distinguished 

 by the divided carapace, the slender neck, usually flexed backward, 

 and the plump posterior processes. 



This species was discovered by Kj*0yer in 1837 and was referred to 

 the genus Lernaeopoda, but he placed a question mark after the genus 

 name and said in the context: ''There is some doubt as to whether 

 this Lernaean should be referred to the geims BracMella ov Lernaeopoda, 

 or whether it should be made the type of a new genus." The species 

 was afterwards described by Beneden under the name Brachiella 

 pastinacae; it has since been noted by Kurz (1877), Brian (1906), 

 Bainbridge (1909), and T. and A. Scott (1913), besides appearing in 

 several lists. In some of these the specific name ended in a vowel, 

 in others in a diphthong; it ended originally in a diphthong. That 

 it really belongs in the genus Charopinus is clearly shown by the 

 backward flexion of the cephalo thorax, by the enlarged ends of the 

 second maxillae, and by the structure of the fii*st antennae and first 

 maxiUae. The description and figures given by Miss Bainbridge^ 

 (1909) are the best that have been thus far published; the following 

 differences are noted in the present specimens. The first antennae 

 have only two joints instead of four, and are exactly Hke those figured 

 by Miss Bainbridge (pi. 9, fig. 8), The teeth on the mandibles corre- 

 spond with those given by Miss Bainbridge, and are a trifle different 

 from the ones figured by Kurz. There are no traces of the ''pair of 

 slender clawed appendages" at the sides of the mouth tube noted by 

 Miss Bainbridge. It would be very difficult to underetand what 

 these would represent, if present. That they can not be "maxillary 

 palps," as suggested by Thomson for his BracTiiella parlceri and 

 quoted by Miss Bainbridge, is at once evident when we reflect that 

 the maxillae already have well-developed palps. In examining a 

 British specimen of Brachiella parlceri Miss Bainbridge failed to find 

 the structures designated "maxillary palps" by Thomson, and in 

 the specimens here described the present author fails to find the 

 structures noted by Miss Bainbridge. It seems probable in both 

 cases, therefore, that they were accidental rather than specific. 



Genus NAOBRANCHIA Hesse. 



Generic characters of female. — Cephalothorax narrow and elongate 

 and well separated from the trunk; a minute but distinct dorsal 

 carapace on the head; trunk broad and well rounded anteriorly, 



> Miss May E. Bainbridge, now the Hon. Mrs. Henn Collins. 

 34843°— Proc.N.M.vol.47— 14 42 



