AMERICAN PARASITIC ARGVLID^WILSON. li^7 



aiig-iilar and very wide posteriorly, the tips of the acuminate lobes 

 beino- so far apart that the sides of the abdomen are ahnost parallel. 

 Anal papilhe of good size and basal. Anterior maxillipcds with an 

 enormous terminal hook, strongly curved; the teeth on the basal plate 

 of the second maxillipcds are small and ver}' blunt. 



Swimming legs all project bej^ond the edge of the carai>ace, which 

 does not cover even the bases of the posterior pair. The tlagella in 

 this species are moderatel3^ developed and terminate in a sharp spine; 

 the endopods and exopods are furnished with a double row of plumose 

 setse; lobes on the basal joints of the posterior legs of good size and 

 boot-shaped. 



In the male the testes are two-lobed, with a pair of spherical ])odies 

 on either side just anterior to the opening of the vas deferens, which 

 Bouvier could not interpret. 



I^ength of smaller male, !.'.»;") nun.; length of cafapacc*, l.iil) nun.; 

 width of carapac-(\ i.^ nun.; length of abdomen, o.O.") mm.; width, 

 0.55 nun. The larger male had a total length of ;> nun. The female 

 was much smaller. These dimensions must of course be taken as those 

 of rather small specimens. 



Color a uniform gi-ay -yellow without any markings. 



IIahif((t. — The three specimens were o])tained by M. (nniy in the 

 month of December between Apure and Arauca, Guiana, and were 

 swinuning freely at the surface of the water, {(reayl — to M. Geay.) 



This finding of them swimming- at the surface, in connection with 

 their small size, might suggest that the}^ were the young of some of 

 the other species. This objection is to my mind answered fully by 

 Bouvier when he says, tirst, that these specimens were sexually mature 

 and therefore nuist possess all the characteristics of the adult even 

 though they were still small in size. And then in the second place we 

 have seen in the development of the only member of the whole family 

 of Argulida? whose complete history is known that the young do not 

 l>ecome sexually mature till they are about one-quarter the size of the 

 adult. This would mean that even if these were the youn^ of some 

 species the adults could not be anywhere as large as the g-reat majorit}^ 

 of the known species of this genus. 



DOLOPS RANARUM, Stuhlmann. 

 Plate XXVII, figs. 89, 90. 



Gyropelth ranarum Stuhlmann, 1891. 

 DolopH ranarum Bovvier, 1899. ■' 



Carapace somewhat ovate, just reaching the base of the abdomen; 

 posterior sinus rather narrow and about one-third the length of the 

 carapace; lo})es well rounded and approaching each other somewhat 

 posteriorly. Abdomen long (about (».5) and narrow% widest at the 

 center, cut for two-thirds its length. Anal sinus peculiar in shape 

 Proc. N. M. vol. XXV— 02 it 



