8 A REVISION OF THE ASTACID.E. 



Vol. I. pp. 4ii2—10.". This paper is the same in substance as the last ; but C. placidus 

 Ha<*. is omitted from the list, and C. Coucsi Streets ? is added. 



1883. The exhibition of living specimens of Camiarus Bartonii from North Grafton, 

 Worcester Co., Mass., at the rooms of the Worcester Natural History Society, is recorded 

 in " Scientific and Literary Gossip," Vol. I. p. 113. The only locality in this State 

 hitherto known was Williamstown, in Berkshire Co. Through the kindness of Mr. F. G. 

 Sanborn these specimens are now in the collection of the Museum of Comparative 

 Zoology. 



1884. In a note " On the so-called Dimorphism in the Cenus Cambarus," in Amer. 

 Journ. Sci., Vol. XXVII. pp. 42—44 (reprinted in Ann. and Mag. of Nat. Hist., 5th Ser. 

 Vol. XIII. pp. 147, 148), 1 suggested that the two forms of the male Cambarus were 

 alternating conditions of the same individual connected with the reproductive seasons, 

 and not dimorphic forms, as was commonly supposed. (See p. 12.) 



1884 Mr. Ralph S. Tarr describes in Nature, Vol XXX. pp. 127, 128, the burrows of 

 C. Diogenes Girard. 



1884. Dr. C C. Abbott, in the American Naturalist, Vol. XVIII. pp. 1157, 1158, 

 takes exception to Mr. Tan's conclusion that the mud chimneys built by ft Diogenes are 

 tin- accidental result of the excavation of the burrows. 



1884. Descriptions of the new species of Cambarus found during the preparation of 

 this Revision, together with a synonymieal list of the species of Cambarus and Astacus, 

 were published by me in the Proceedings of the American Academy of Arts and Sciences, 

 V.l. XX. pp. 107-158, December, 1884. 



Dr. Hagen's Monograph must ever remain the foundation for all .sys- 

 tematic work on the North American Astacida). The types of all his species 

 are in the Museum of Comparative Zoology, and have been constantly 

 before me in the preparation of the present Revision. With far ampler 

 material at my disposal than fell to Dr. Hagen's lot, I have seldom had 

 occasion to differ from him in his conclusions concerning the species known 

 to him. Thirty-two species of Cambarus are described by Dr. Hagen. Of 

 these, eleven are described as new species ; viz. C. fallax, Lecontei, versvtus, 

 ktncifer, virilis, placidus, Juvenilis, obscurus, immunis, eztraneus, and obesus. Of 

 these, C. placidus and C. juvenilis are in my opinion only forms of the vari- 

 able species C. rusUcus Gir.; C. obsciirttx, a local variety of C. propinquus Gir. 

 C. obesus is the Bame as C. Diogenes Gir. The remaining species included in 

 Hagen's memoir are C. aeuius Gir., Clarhh Gir., troglodytes (LeC), Bhndingii 

 (Harlan), spiculifer (LeC), angustatus (LeC), maniculatus (LeC), penicillatus 

 (LeC), Wiegmanni Erichs., pellucidus (Tellk.), affinis (Say), propinquus Gir., 

 ruslicus Gir., Bartonii (Fab.), robustus Gir., Nebrascensis Gir., latimanus (LeC), 

 Mezicanus Erichs., Cubensis Erichs., advena (LeC), and Carolinus Erichs. 

 ('. maniculatus, Nebrascensis, Mexicanus, and Cubensis were known to Hagen 

 mils through the descriptions of the original authors of the species. C. ac\ - 



