24 A REVISION OF THE ASTACID^. 



The four type specimens, collected by Dr. H. Bryant, are 1 $ form I., 

 2 <? form II., 1 9. The measurements given by Hagen are those of the 

 largest specimen, <? form II. This is the largest specimen I have seen. 

 C. ftillax is very near C. Blandingii, which it seems to replace in the State 

 of Florida. It is easily distinguished from the latter species by the male 

 appendages, which are curved backwards at the end, and armed with only 

 minute teeth at the tip. The distal margin of the proximal segment of the 

 telson is armed on each side with three or four spines. In a few specimens 

 from Hawkinsville, St. John's River, Fla., the acumen of the rostrum is 

 lengthened, the lateral spines of the rostrum are stronger, and the portion 

 of the carapace behind the cervical suture is shortened. The specimens 

 thus approach C. Leeontei. The shortening of the posterior part of the 

 carapace is not so great as in C. Leeontei, the areola is narrower, and the 

 male appendages do not differ from those of the typical G.faUax. In the 

 ordinary form of C.fallax the distance from the tip of the rostrum to the cer- 

 vical groove is twice the distance from the cervical groove to the hind border 

 of the carapace. In the abnormal specimens just noticed the anterior dis- 

 tance is two and one third times that of the posterior ; in C. Leeontei it is 

 two and one half times. In many specimens, contrary to Hagen' s descrip- 

 tion, the antennae are much longer than the body, and in well-developed 

 males of the first form the chelae are inflated and cylindrical. Specimens 

 of this species, now in the Museum of the Peabody Academy of Science. 

 Salem, were collected by C. J. Maynard, in Blue Spring, St. John's River, 

 a mineral spring impregnated with sulphur and magnesia, — temperature 

 70° Fahr. They were clinging to the under side of leaves. 



3. Cambarus Hayi. 



Plate I. ili,-. 4, Plato VII. figs. 3, 3', 3a. 3a'. 

 Cambarus Hayi, Faxon, Proc. Amer. Acad. Arts ami Sri., XX. 10S, 18S4. 



Male, form 1. Rostrum broad, triangular, excavated, sparsely pubescent 

 above; acumen short, lateral spines moderate. Carapace punctate above, 

 granulated on the sides, the granules filiate. Lateral spines slightly devel- 

 oped in fully-grown individuals, more prominent in the young. Areola 

 narrow. Abdomen broad, shorter than the cephalo-thorax. Pleural angles 

 rounded. Proximal segment of telson with two spines on each side of the 

 distal border. Hind margin of telson slightly concave. Anterior process 



