505. 

 PLATYSTOMA SEMINATIONIS. 



Order Diptera. Fam. Muscidae. 



Type of the Geiius, Musca seminationis Fab. 

 Platystoma Meig., Lat., Curt. — Dictya Fab. — Musca Fab. 



AntenncB inserted near the middle of the face, approximating', 



small, deflexed and 5-jointed, basal joint short and broad, 2nd 



larger somewhat cup-shaped, furnished with spiny bristles, 3rd 



larger subovate, velvety, 4th minute attached to the top of the 



3rd near the base, 5 th a long seta sparingly pubescent (3). 



Trophi inserted in a large cavity beneath the head and porrected 



obliquely (2). 



Labrum short broad, hollow and notched at the apex (1 b). 



Tongue very minute (1 c). 



Palpi exserted, large pilose, clavate and compressed {f). 



Lip exserted, very large thick and bilobed, the lobes very hairy 



Head suborbicular ; hypostoma oblique, concave and naked : eyes re- 

 mote, lateral, and elongated, reaching the back part of the head : 

 ocelli 3 in triangle at the base of the head (2 the profile, 2* front 

 view). Thorax a little larger than the head, nearly globose : scu- 

 tellum transverse-ovate. Abdomen small subcordate and 4-jointed : 

 oviduct exserted and telescopiform. Wings ample, divaricating and 

 vibrating, with 2 transverse nervures, one at and another beyond the 

 middle (9) : alulae small : halteres naked, small and capitate. Legs 

 nearly alike, rather short and stout : tibiae compressed, dilated 

 towards the apex : tarsi rather broad and 5-jointed, basal joint the 

 longest, the others very short and lunulate in the anterior pair, the 

 terminal joint obovate : claws short, pulvilli bilobed. 



\ 



Seminationis Fcti. — Curt. Guide, Gen. 1311. 1. 



Black with a few hairs of the same colour, long on the back 

 part of the head, thorax and scutellum ; eyes margined white 

 with a ferruginous streak above ; thorax, scutellum and abdomen 

 cinereous ochre above, punctured with black, underside of the 

 latter ochreous, excepting the apex, which is entirely black : 

 wings black, with a yellowish tinge, the costa inclining to 

 ferruginous at the base, covered with numerous white spots 

 varying in size, leaving a black space across the middle nearly 

 free from spots, and sometimes another towards the apex less 

 distinct ; halteres fuscous. 



In the Author s and other Cabinets. 



Meigen has erroneously referred Moses Harris's figure of 

 cur insect to the P. umbrarum Fab., a species hitherto not 

 detected in this countr}'. It is stated to be not uncommon in 



k 



