of the Family Halacaridge. 179 



nodose, with the claws terminated by two teeth, the larger of 

 which is inserted nearly at a right angle; destitute of a 

 ciliated comb. Rostrum small, with the epistome cut squarely 

 at the base of the palpi, the hypostome prolonged into a bi- 

 valve spatuliform furrow, within which the mandibles slide, 

 each terminating in a long seta, which passes beyond the 

 rostrum. Anus terminal. Total length 0*50 millim. 



Hob. Shores of France : Roches de Castouillet (near Le 

 Croisic), by dredging with the aid of swabs (Chevreux) ; two 

 individuals. 



Genus Halacarus, G-osse, 1855. 



Halacarus, Gosse (1), p. 27. 



Halacarus, Copidognatkus, and Leptopsalis, Trouessart (7), p. 753. 



Char. Rostrum elongated, cylindro-conical ; palpi free, 

 parallel, articulated upon the sides of the rostrum, composed 

 of four joints, of which the third is much shorter than the ter- 

 minal joint, which is strongly conical, elongated, often styli- 

 form, and furnished with three divergent seta? upon its inner 

 margin ; second joint the longest of all. Hypostome in the 

 form of a more or less elongated bivalve furrow, triangular or 

 truncated in front. Mandibles (chelicerae) terminated by a 

 single finger, generally hooked. Claws of the feet inserted 

 directly upon the tarsus without any additional joint. 



The number of species of this genus is already considera- 

 ble, at least seventeen, eleven of which occur upon the French 

 coasts. This is the reason that we attempted to subdivide it 

 by forming the genera Gopidognathus and Leptopsalis, the 

 former founded upon a species (G. glyptoderma) in which the 

 mandibles are very strong, and terminate in a straight, knife- 

 shaped finger with a serrated blade. But a thorough exa- 

 mination of several allied species having shown this cha- 

 racter to be rather variable, we have preferred to reunite 

 this species with the genus Halacarus proper. The genus 

 Leptopsalis includes two species in which the last joint of the 

 palpi is bifid, simulating a little forceps ; this character seems 

 to be of sufficient importance for us to retain this group as a 

 subgenus. 



Subgenus Halacakus, proper. 



Char. Last joint of the palpi terminating in a single 

 point. 



In the enumeration of the species we shall follow the order 

 and arrangement adopted by M. Lohmann in his Mono- 

 graph (8). 



