THAXTER. NEW LABOULBENIACEAE. 29 



is bluntly pointed and somewhat narrower toward the base, the distance 

 from tip to tip often twice the diameter of the perithecium. In a few 

 specimens the receptacle and perithecia are somewhat evenly suffused 

 with smoky brown. Perithecia 75-85 X 25-30 jx, the appendages 18- 

 22 ix. Receptacle 165-200 X 55-70 /x. Total length 235-275 fx. 



On the inferior surface of the abdomen of Philonthus atriceps Sharp. 

 Jalapa, Mexico. Sharp Collection, No. 1112. Specimens, apparently 

 normal, sometimes occur in which the tips of the perithecia are blunt 

 and unmodified. 



Dichomyces Homalotae nov. sp. 



Form short and stout. Basal cell geniculate, more or less suffused : 

 the lower tier more or less, sometimes wholly, suffused with reddish 

 brown ; the margins darker, more or less translucent, without contrasts, 

 the outline somewhat uneven, the transition to the middle tier indicated 

 by a distinct prominence: the middle tier consisting of from nine to 

 (rarely) thirteen cells, hyaline or subhyaline, with slight lateral suf- 

 fusions ; the marginal cells ending in a slight hyaline rounded projection, 

 seldom extending higher than the venter of the somewhat suffused 

 curved antheridia : the upper tier relatively small, the cells subequal, 

 hyaline, asymmetrical, owing to the development of but one perithecium ; 

 the appendages often equalling, or exceeding the perithecium in length. 

 Perithecium characteristically short and stout, inflated below, sometimes 

 oval, tapering somewhat abruptly distally, to the rather broadly truncate, 

 or slightly rounded unmodified apex. Spores 33 X 3 /x. Perithecia 

 65-75 X 25-30 /a. Receptacle 70-90 X 40-55/1. Total length 125- 

 165 fx. 



On all parts of Homalota sordida Marsh. Fresh Pond, Cambridge. 

 First observed by Mr. Bullard. 



Peyritschiella Xanthopygi nov. sp. 



Basal cell of the receptacle very small, or hardly distinguished from the 

 foot : the first tier consisting of three subequal cells without appendages, 

 the middle one somewhat shorter than those on either side of it : the 

 second tier asymmetrical, consisting of three subequal median cells, the 

 margins of the two outer free below for nearly half their length and 

 coincident with the margins of the tier below, the appendiculate " margi- 

 nal " cells, about three to five on either side, separated from them as 

 usual by oblique septa ; the first on the right bearing the large, slender, 

 pointed, nearly straight purplish antheridium : the upper tier consisting 



