422 THE CANADIAN ENTOMOLOGIST 



the base of the lamellae of the fourth ventral plate is very promi- 

 nent forming the posterior face of the somewhat conically raised 

 extremity of the base. The "brushes" of the lamellae are promi- 

 nent even when the genital segments are in their normal position, 

 and may be seen filling in the space between the forceps and the 

 ventral portion of the fourth notum. The marginal bristles of the 

 third abdominal segment which are present in most species of Sar- 

 cophaga, are lacking, though sometimes a few, short, decumbent 

 bristles may be discerned. If the penis is examined a weakly 

 chitinized projecting process is seen extending upwards from the 

 dorsal, distal portion. This bends abruptly forward and divides 

 in to a Y. When specimens are fresh, a profile view shows this 

 process raised above the penis head, but when dry it is often 

 applied to it. The four sternopleurals of the female are distinctive. 



S. cooleyi is very closely related to an undescribed species, the 

 same mentioned by Dr. Felt in his annual report for 1912 (New 

 York State Museum Bulletin 165, pp. 80-82), under the name of 

 S. georgina Weid., a synonym of S. hcemorrhoidalis Meig. This 

 undescribed species has a wide distribution throughout the United 

 States. 



While engaged on investigation for the Montana State Board 

 of .Entomology during the past summer, the writer bred this 

 species extensively from decomposing fish. It was also captured 

 in privies and was common around garbage, especially if the latter 

 contained fish. In one experiment, in which two hundred larvae 

 were used to determine the length of the larval stages, not a single 

 adult emerged but numerous chalcid parasites were raised from 

 the pupae. 



Explanation of Plate XXVI. 



(All drawings made with camera lucida). 



Fig. 1. Side view of genital segments of male showing penis 

 forceps, anterior and posterior claspers accessory plate. 



Fig. 2. Ventral view of fourth ventral plate and profile view 

 to show elevation at posterior extremity of base. 



Fig. 3. Posterior view of forceps. ' 



Fig. 4. Genital segments of female (made from a specimen 

 with genital segments partly expanded). 



