No. i.] SOME MUSCINAE OF NORTH AMERICA. 



FIG. 18. 



the middle tibia, near the extensor border, a series of bristles 

 extending from base to apex ; the basal half of the series are 

 very tiny but stout as compared with their length, real little 

 spines ; at about the middle of the series the form changes 

 gradually to that of a delicate and moderately long bristle. 

 This arrangement is very like that of the European M. Jior- 

 torum Fall. My specimens of 

 this species are from Jamaica, 

 C. W. Johnson, and from Mex- 

 ico, O. W. Barrett. 



The other species agrees with 

 the descriptions of Pyrcllia 

 scapulata Bigot (Fig. 19) and P. 

 flora Bigot. The middle tibia 



of the male has some noteworthy structures. On the anterior 

 surface at the base is a tubercle about 0.3 mm. (one-seventh 

 the length of the tibia) long and half as broad, its long diameter 

 parallel to that of the tibia. On this tubercle is a row of six or 

 eight very short thick spines, and in some specimens a second 



row, flexad the first, of about 

 four similar but much smaller 

 spines, can be made out. From 

 the apical end of the tubercle 

 the principal row is prolonged 

 as a series of about equal and 

 equidistant, much more delicate 

 spines, as far as the apex of 



the tibia. Just at the junction of the posterior and flexor 

 surfaces there are three large bristles ; one is at the junc- 

 tion of the basal and middle thirds, the second at the middle 

 of the tibia, the third at the junction of the middle and apical 

 thirds. My specimens of this species are from Jamaica, col- 

 lected by C. W. Johnson. The name scapulata has priority. 



FIG. 19. 



