394 NEW TOEK STATE MUSEUM 



Appendages over the labrum lanceolate and four or five times 

 las long as vifide, ventral comb of last segment vs^ith 21 bairs 



(Bm-opean) pallida 



4 " One of the four antenmal bristles markedly shorter than the 



rest " plumlcornis (Europe) 



The four anteunal bristles of equal length ; anal segment vyith 



four dorsal hairs plumlcornis, var. americana 



The larva of O. t r i v i 1 1 a t a described by Dyar in, N. Y. Ent. Soe. 

 Jour. 10:201 is said to have but 2 dorsal haiirs on anal segment. 



Pupae 



" Extraordinarily elongate abdomen vsrhich terminates in two 

 paddlelilfe appendages, loosely ciliate outvsrardly ". .-appendiculata 



Abdomen of moderate length, see figure ; paddles vi^ith short cilia 

 on the inner margin. plumlcornis 



Imagos 



1 Wings -with dark markings (2> 



Wings unmarked (4> 



2 Wings with several cross bands. Length of insect 1.5mm. . . . 



Oorethrella brakeleyi 

 Wings with numerous dark spots (3) 



3 The apex of both femora and the tibiae, and the base also of 



the tibiae, black, antennae with subfuscous hairs. Length 



4.5mm trivittata 



Legs punctate with numerous small brown spots. Antennae 

 with yellowish hairs punctipennis 



4 Yellowish white species; legs white and spotless a 1 b i p e s n. sp. 



Pale brown or reddish yellow species plumlcornis. 



Judging from the description, the larva of ap p e n d 1 c u - 

 lata differs greatly from all the known Corethra larvae, and 

 F. Meinert in De eucephale Myggelarver says in regard to its pupa 

 that the figure given by Herrick resembles that of a Chironomid 

 rather than a Corethra. In the same paper Meinert expresses 

 the opinion that f u s c a is- but a darker variety of pluml- 

 cornis; and attributes the differences in the larva to an error 

 of Staeger, assiuming that the latter described some other 

 species. 



Corethra appendiculata Herrick 

 Minn. Geol. Nat. Hist. Sur. 1884. p.l9, pl.5. 



The adult not bred. Larva as follows: 



Form is more slender than plumlcornis. The tracheal 

 vessels are of a different form and color, and viscera have obvi- 

 ous differences. . . Shape of the head is slender and attenu- 

 ated toward insertion of the antennae. Antennae are shortish 



