CALIFORNIA ACADEMY OF SCIENCES. 



327 



small streams. They are amongst the most minute of 

 Trichopterygiche, and are probably very numero^^s in spe- 

 cies, although from the great care requisite in collecting 

 them the number of described species will in all probability 

 increase very slowly. 



It has been stated by Dr. Horn (Ent. Amer. I, p. 108) 

 that three of the species of Trichopter\ gid;e described by 

 me (Cont. II. p. 162-166), viz: Ptilium fangicola, Trichop- 

 teryx funginus and T. longipennis, are synonymous with P. 

 Horniarum Matth., T. discolor Hald., and T. parallela Mots., 

 respectively. In order to show that in all probability this is 

 not the case, I quote inparallel columns several salient dif- 

 ferences as recorded in the descriptions of Mr. Matthews 

 and those published by me in the work above mentioned. 



P. Horniarum Mattb. — Obloug, 



castaueous; antennae dark yellow; 

 legs bright yellow; under parts pale 

 castaneous with the mouth, hinder 

 parta of the metasternum and ter- 

 minal segments of the venter flaves- 

 cent. Leugth, .37 mm. 

 Texas. 



P. fungicola Cas. — Form elonga- 

 ted. Color above piceous-black, be- 

 neath very slightly paler; oral organs, 

 legs and parts of the prosternum pale 

 reddish-flavate; antennfe black, basal 

 joints darkflavo-testaceous. Length, 

 .45 mm. 



Pennsylvania. 



The abdomen in fungicola does not project beyond the 

 elytra as in the majority of species of Ptilium, and I noticed 

 no flavescent parts of the metasternum and abdomen, as 

 mentioned hy Mr. Matthews. 



T. discolor Hald. — Black, with the 

 elytra testaceous, sparingly clothed 

 with fiilvous hair; thorax moderate, 

 much broader and longer than the 

 head, widest near the 'base, black 

 ■with all the margins yellow; sides 

 moderately rounded, hinder angles 

 pale and much produced; elytra tes- 

 taceous, short, rather shorter and 

 narrower than the head and thorax; 

 sides nearly straight; closely but ir- 



T. funginus Cas.— Piceous-black, 

 elytra becoming rufo-piceous toward 

 the tiijs, which are margined with 

 fulvous; legs and basal joints of the 

 antennPB rather dark piceo-testace- 

 ouR, remainder of the antennae dark 

 piceous-brown. Pubescence rather 

 abundant, cinereous. Sides of the 

 prothorax nearly straight anteriorly, 

 very arcuate posteriorly; posterior 

 angles very moderately produced. 



