164 PROCEEDINGS OF THE AMERICAN ACADEMY. 



stalk-cell and discharging at the same level into the efferent tube. 

 Perithecia stalked and normal. 



The characters of this genus correspond exactly to those of Core- 

 thromyces Quedionuchi which occurs with it on the same host, and in 

 general to that section of Corethromyces formerly separated under 

 Sphaleromyces, except that the lower branches of the appendages 

 bear conspicuous, typically developed compound antheridia. It 

 seems altogether probable that certain of the species hitherto placed 

 in Sphaleromyces, and in which the presence of antheridia has not 

 yet been definitely recognized, may find a place in the present genus 

 when their antheridial characters are known. A careful reexamination 

 of my material of these species has, however, failed to show any indi- 

 cation of the conspicuous antheridia which occur in the present 

 instance. 



Mimeomyces decipiens nov. sp. 



Perithecium pale translucent yellowish, the basal cells relatively 

 large and clearly distinguished, the ascigerous part usually bent 

 slightly toward the appendages, distally slightly inflated, symmetrical, 

 conical; the tip hardly distinguished, terminating in a small sub- 

 truncate apex: stalk-cell short, broader than its length. Basal cell 

 of the receptacle elongate, rather abruptly broader distally, con- 

 colorous with the perithecium or more or less deeply and completely 

 suffused with blackish brown, sometimes quite opaque; the subbasal 

 cell small, subtriangular. Appendage consisting of from four to five 

 obliquely superposed cells, subequal in length, the distal ones smaller, 

 the basal without appendages, the subbasal and often the cell above 

 it bearing each a single compound antheridium on a short stalk-cell. 

 Perithecium (sporogenous portion) 55-65X24 fj,, including basal and 

 stalk-cells 75-95 /jl. Main appendage 50-55 fx, its longest branches 

 60 iJL. Receptacle 50-70 yu, basal cell (longest) 60 /j,. Total length to 

 tip of perithecium 125-150 yu. Spores about 30X2.5 (measured in 

 ascus). 



On legs and abdomen of Quedius sorecocephalus Bernh. (nov. sp.), 

 Llavallol, No. 1520. 



The general form and coloration of this species is very similar to that 

 of Corethromyces Quedionuchi which may occur with it, but the color 

 and the form of the tip of the perithecium, as well as the conspicuous 

 antheridia distinguish it at a glance. One or more accessory anther- 

 idia are sometimes present near the base of the appendage. The host 

 has been determined as a new species of Quedius by Dr. Bernhauer. 



