386 CRA\TISHES. 



Cambarus bartonii montanus (Girard). 



In looking over any extensive collection of Cambarus bartonii from the Alle- 

 ghany Mountain region of Virginia and West Virginia one is struck by the 

 tendency of the material before him to fall into two sets of forms, one character- 

 ized by a rather narrow areola, sparsely sown with impressed points or dots 

 which incline to a serial arrangement in three or four longitudinal rows; while 

 in the other set the areola is shorter and proportionally broader, and its field 

 is thickly strewn with innumerable dots. On further examination it will be 

 seen that the narrower areola usually goes with a shorter and broader rostrum, 

 a more depressed and oval carapace and a narrower antennal scale. These two 

 forms are often found in the same locality and with these alone in view one might 

 be justified in deeming them two well-differentiated species, but it soon becomes 

 clear that in other places specimens are found that combine in a most perplexing 

 fashion the features of our two supposed species. 



The second of the two forms above noticed, the one with the s,horter and 

 broader and more tliickly punctate areola and longer rostrum is the one too 

 curtly diagnosed by Girard under the name of Cambarus montanus. 



Girard's description of C. montanus is as follows: — ■ "Antennae more elon- 

 gated and more filiform than in C. Bartonii. Rostrum intermediate in shape 

 between the latter and C. carolinus, being proportionally longer than in C. Bar- 

 tonii and shorter and less tapering than in C. carolinus. Dorsal sutures of the 

 carapace more apart than in both of the latter species. 



"Localities. — Within the Alleghany ranges in Virginia and Maryland: 

 tributaries of James River in Rockbridge Co. (Va.); Shenandoah River in 

 Clarke Co. (Va.), and Cumberland (Md.) of the hydrographical basin of the 

 Potomac ; Sulphur Spring, Greenbrier River, an affluent of the Kenhawa River 

 (Va.) [now W. Va.] of the Ohio basin." 



Wlien Dr. Hagen was preparing his Monograph of the North American 

 Astacidae in 1868, he had the opportunity to examine one of Girard's types of 

 C. montanus from Greenbrier River, W. Va., sent to him by Wm. Stimpson who 

 then had the types from the Smithsonian Institute in Chicago, where in 1871 they 

 were most unfortunately destroyed by the disastrous conflagration of that year. 



Sixteen years later, while I was revising the Astacidae, I had the advantage 

 of close personal intercourse with Dr. Hagen and free use of his notes and memo- 

 randa. The identity of Girard's Cambarus montanus is thus assured by an 

 unbroken tradition. Neither Dr. Hagen nor myself in my earlier publications 

 esteemed this form worthy of even a subspecific name, although its characters 



