NEW LABOULBENIALES. 697 



broader where it joins the tip, from which it is not distinguished; the 

 tip strongly convex externally, straight or slightly concave on its 

 inner side; the apex very short, hyaline, abruptly distinguished, 

 papillit'orm, slightly prominent externally above the usually persistent 

 insertion of the trichogyne, its outline more or less evenly rounded, 

 the lips not at all prominent. Spores about 30 X 4 /x. Perithecia: 

 basal and stalk-cell portion about 18 X 27 m; venter, average 60 X 

 35 /i, maximum 75X40/x; distal portion about 45-50 X 11m- 

 Receptacle 45 X 20-22 ^x, maximum length SO ix. Appendage typi- 

 cally 60-70 X 16 /x, sometimes smaller. Total length to tip of perithe- 

 cium, average 180 ju, maximum 225 ix. 



On legs, wings, and thorax of Parydra quadrituherculata Linn., 

 No. 1804, Fayetteville, Arkansas. 



Although this species has no very striking peculiarities, it is well 

 distinguished by its stout form, short subbasal cell, large many celled 

 appendage, and stout perithecium; the well distinguished stout neck- 

 portion strongly curved and ending in the small, abruptly distin- 

 guished, button-like apex. It varies very slightly, individuals on the 

 wing being somewhat longer. 



On Oscinidae. 



Stigmatomyces constrictus Thaxter. 

 Syn. S. Elachipterae Thaxter. 



This species, the original host of which from the papuan region was 

 not determined, proves to be characteristic of various genera of the 

 Oscinidae, and an examination of a very large series of specimens 

 leaves no doubt as to its identity with S. Elachipterae, which was 

 found on a species of the oscinid genus Elachiptera in New Hampshire. 

 It is one of the most variable of all the species of Stigmatomyces, and 

 the peculiarly narrowed base of the subbasal cell, which suggested 

 the specific name, proves to be quite as often wholly lacking, as it is 

 present. The general habit may be short and stout in well developed 

 individuals which measure only 150 /x in length; while long slender 

 forms occur, which may reach a length of 450 /x, although such are not 

 often met with. The type of appendage is always the same, and is 

 very characteristic; but the number of antheridia is subject, as usual, 

 to slight variations. The perithecium, especially its termination. 



