1915.] m 



anteriorly. Meso- and metathorax separate from one another. Metathorax 

 separated from 1st abdominal se<>-ment by a membi'anoiis area. Sternal markings 

 well defined. 1st abdominal sternite reduced, 2nd different in size, shape or 

 chaetotaxy (sometimes in all these respects) from the others. Plenrites well 

 developed, biit with no internal thickening. 



(J with characteristic genitalia — a moderately long basal jilate, continuous 

 distally with a broad truncately rounded lamina at the base of which the stout 

 apically recurved paramera are set. 



$ sometimes with simple transverse abdominal tergites, but quite as often 

 the sexes are dimorphic here, one or more of the tergites being backvvardly 

 produced. 



Hosts — Passerines, especially the more advanced groups, e.g., crows. 



Genotype : M. victrix sp. n. 



The above complex of characters svifliciently indicates one of the 

 most interesting Menoponid groups. A number of species have been 

 described by various authors as Me)io})on or Colpocephalum. 



Myrsidea may ultimately have to be further split up. Possibly 

 the sexually dimorphic should be separated from the simpler forms. 

 The genotype is one of the most specialised of the group, as the 2nd 

 sternite bears strong processes with heavy asters of spines, and no fewer 

 than four of the tergites are modified. Myrsidea and Menacanthua 

 occur together quite often on the same individual host. 



Myrsidea victrix sj). n. 



(J . Head. 4 long bristles on the temples, 2 rather short at the middle of 

 the occiput. 1 minute bristle where the occiput crosses the prothoracic edge, 

 and another pair of similar bristles a short distance from the edge. On each 

 side of the qiiadrate posterior ventral sclerite are 4 bristles, 1 strong and 

 long below the occiput and 3 much weaker and shorter in front. 6 short 

 bristles in 2 parallel rows (3, 3) in the space between the antennal grooves. 



Thorax. Pronotum, 3 short spines at lateral angle. On the posterior 

 edge a row of stout elements, viz., a spine, 4 bristles and a spine. Mesonotum 

 bare, save for a minute spine posteriorly on each side of the median line. 

 Metanotiun with two such spines on each side, separated by a naiTOw unchiti- 

 nized belt from the mesonotum and almost straight across the abdomen. 1-2 

 spines and a long bristle at the angles, and about 12 long bristles on the 

 posterior edge. Prostex'num bare, with a pear-shaped mark. Mesosternum and 

 metasternum with large quadrate marks sending out arms between the coxae. 

 Tlie mesosternum bears anteriorly 6 short spines, and 8 longer bristles. 



Abdomen. Tergites, pleurites and sternites well developed. The stemites 

 bear 5-8 spines or bristles. On the anterior segments are chiefly short spines. 



