174 U.S. NATIONAL MUSEUM BULLETIN 2 59 



HiBBARD, C. W. 



1960. An interpretation of Pliocene and Pleistocene climates in North 

 America: President's address to the Michigan Acad. Sci., Arts, 

 and Letters. In Michigan Acad. Rep. for 1950-1960, pp. 5-30. 

 Holmes, S. J. 



1909. Description of a new subterranean amphipod from Wisconsin. Trans. 

 Wisconsin Acad. Sci., Arts, and Letters, vol. 16, pp. 77-80. 



HOLSINGER, J. R. 



1963. Annotated checklist of the macroscopic troglobites of Virginia with 



notes on their geographic distribution. Bull. Nat. Speleol. Soc, 

 vol. 25, pp. 23-36. 



1964. The biology of Virginia caves, pp. 57-74. In H. H. Douglas, Caves 



of Virginia. 

 1966. Subterranean amphipods of the genus Stygonedes (Gammaridae) 

 from Texas. Amer. Midi. Nat., vol. 76, pp. 100-124, figs. 1-94. 



HUBRICHT, L. 



1943. Studies on the Nearctic freshwater Amphipoda, III: Notes on the 

 freshwater Amphipoda of eastern United States with description 

 of ten new species. Amer. Midi. Nat., vol. 29 pp. 683-712, pis. 8, 9. 



1959. Malacostraca (Amphipoda), pp. 876-878. In W. T. Edmondson 



(ed.) Ward and Whipple's freshwater biology. 



HuBRiCHT, L., and Mackin, J. G. 



1940. Descriptions of nine new species of fresh-water amphipod crustaceans 



with notes and new localities for other species. Amer. Midi. Nat., 

 vol. 23, pp. 187-218, fig. 11. 

 HussoN, R. 



1960. Les Crustac^s P^racarides des eaiix souterraines. Archives Inst. 



Grand-Ducal Luxembourg, vol. 27, pp. 107-119. 



Hynes, H. B. N. 



1955. The reproductive cycle of some British freshwater Gammaridae. 

 Journ. Anim. Ecol., vol. 24, pp. 352-387. 



Jersche, G. 



1963. Zur Artfrage und Variabilitjit von Niphargus tatrensis Wrzesniowski. 



Zeit. Zool. Syst. Evolutionsforschung, vol. 1, pp. 240-276. 



Johnston, P. M. 



1964. Geology and ground-water resources of Washington, D.C., and 



vicinity. Geol. Surv. Water-Supply Pap. 1776, 97 pp. 



KUMMEL, B. 



1961. History of the earth, 610 pp. 



KUNKEL, B. W. 



1918. The Arthrostraca of Connecticut. Bull. Connecticut Geol. and Nat. 

 Hist. Surv., vol. 26, pp. 1-261, fig. 21. 



Mackin, J. G. 



1935. Studies on the Crustacea of Oklahoma, III: Subterranean amphipods 

 of the genera Niphargus and Borula. Trans. Amer. Microscop. 

 Soc, vol. 54, pp. 41-51, pi. 10. 



1941. A key to the species of Amphipoda of Oklahoma. Proc. Oklahoma 



Acad. Sci., vol. 21, pp. 29-30. 



Maguire, B., Jr. 



1964. Crustacea: A primitive Mediterranean group also occurs in North 

 America. Science, vol. 146, pp. 931-932. 



