244 PROCEEDINGS OF THE AMERICAN ACADEMY. 



firm the statemeut of Baiuier, and so far as the zygosporic hyphae can be 

 traced they remain separate. The difficulties in cultivating this obligate 

 parasite has deferred the determination of its thallic character. The very 

 common occurrence of zygospores would seem perhaps to indicate a homo- 

 thallic condition. 



Syncephalis Cornu van Tieghem and Le Monnier. 



Van Tieghem ('75j found the zygospores of this species which had 

 infected a gross mixed culture oi Mucor plasmaticus and Pilaira anomala. 

 " In formation of a zygospore a slender mycelial branch swells at its 

 summit and dichotomizes irregularly much as when it prepares to pro- 

 duce a sporangial tube. While the other branches of this ' palmure ' 

 remain short and form expansions like fingers of a glove, two of them 

 grow more in length, place themselves parallel to each other for a very 

 short distance, and generally in contact in their lower part." The text 

 and Figure 88 indicate a homothallic condition. However in Figures 89 

 to 92, although the zygophores are not traced to their origins, enough is 

 given to show that they arise at least at some distance from the ' ' pal- 

 mure " mentioned above. 



Bainier ('82) describes the zygospores of this species under the name 

 of S. curvata. " Zygospores form in the same fashion as in S. Cornu, 

 and the description of van Tieghem may apply here." The zygophoric 

 branches are made to arise from the same base or from two distinct 

 filaments of the mycelium, and these two conditions are shown in Figures 

 9 and 10 respectively. 



Leger ('96) reports zygospores, but adds nothing of interest to van 

 Tieghem's account. 



Thaxter ('97) describes the mature zygospores which were found on 

 mouse dung, but the origin of the zygophoric hyphae is not shown by the 

 figure. 



In February of the present year the writer found abundant zygospores 

 which correspond to figures of this species in a rat dung culture where 

 S. cordata and S. depressa had also developed their sporangial fructifica- 

 tions. So far as the zygophoric branches were traced they remained 

 separate. 



Syncephalis reflexa van Tieghem. 



Thaxter ('97) found zygospores of this species on a culture of mouse 

 dung. The figures do not show the origin of the zygophoric hyphae. 



