ENTOMOPHTHOREAE OF THE UNITKI) STATES. 



17.1 



was colored a vivid pea green, a circumstance thai can hardly be due to any coloring 

 matter from the host, which is of a pale yellowish tint. A similar coloring will be noticed 

 presently tinder M. dipterigena. 



The formation of the resting spores in this species has already been mentioned (p. 147). 

 The instances figured (figs. 214-217) were taken from two leaf hoppers, the only speci- 

 mens that T have examined in which the development of the spores was at exactly the 

 proper point for observing their origin. The differences apparent between this process 

 and thai figured by Brefeld 1 are, in my opinion, merely the result of the difference ex- 

 isting between the conditions present in either case; the totally dissimilar nature of the 

 hos1 being in itself a sufficient explanation. It should be noticed also that in the legs of 

 these same specimens the hyphae were long and continuous, and, although no resting 

 spores had begun to develop in them, an occasional anastomosis was apparent; while the 

 same is true of the preceding species (JE. occidentalis) in which resting spores were ob- 

 served in a similar situation in connection with hyphae which showed anastomoses here 

 and there. 



Empusa (Entomophthora) Aphidis Hoffman. 

 PI. 18, figs. 220-240. 



Entomophthora Aphidis, Hoffman in Fresenius I. c. B, p. 208, figs. 59-67. Winter 

 I. c. Sorokin I c. C, p. 213, figs. 593-594, 634:; I c. d, p. 60, plate n, figs. 14-18. 

 NowakowsM I. c. B, p. 164, figs. 59-62. 



Tarichium Aphidis, Cohn I. c. B, p. 84:. 



Entomophthora ferruginea, Phillips I. c, p. 4, plate in, figs. 1-13. 



Conidia ovoid to elliptical or subfusiform; commonly asymmetrical and very varia- 

 ble; with papillate base and containing numerous oil globules. Average measurements 

 25 X 12/i, maximum 16 X 40,«. Conidiophores digitate, often simple. Hyphal bodies spher- 

 ical, germinating in all directions and giving rise to numerous contorted hyphae which 

 grow into conidiophores. Gystidia rather slender and tapering at their extremities. 

 Secondary conidia like the primary, or short ovoid with a single large oil globule. Best- 

 ing spores "spherical, 33-45 /Jt in diameter and borne terminally or laterally on hyphae" 

 (Fresenius and Sorokin). Host attached to substratum byrhizoids, few in number, and 

 usually terminating in a disc-like expansion. 



Hosts. Ilemiptera: Aphides of numerous genera. 



Habitat. Maine, New Hampshire, Massachusetts, N. Carolina, Washington, D. C, 

 Europe. 



It is of course impossible to determine whether the description of Fresenius 2 really 

 refers to this species or to other forms found upon aphides and producing similar rest- 

 ing spores ; yet there can be no doubt that the conidia first described by Winter 3 and 

 subsequently described and figured by Nowakowski are identical with those of the form 

 above described. Although I have not myself observed the resting spores of this spe- 

 cies, they are described by Winter and Sorokin as spherical, so that the assumption is 

 justified that in the present instance we are dealing with the true M. Aphidis, which must 



1 1. c. D. H.c.B. 3 Lc. 



