198 [February, 



side just in front of the widest part, there are also two black vittse along the middle, 

 of somewhat irregular outline and narrower in front, and there is also a black mark 

 of quadrate form in front of the scutellum, which causes the central yellow vitta to 

 be bifurcate at the base ; the ochraceous portions have quite the appearance of a 

 coarse squamosity, but this appearance is really only due to excessively fine inter- 

 ruptions caused by a scratching of the surface, a few very short pallid setse are 

 distributed over the surface, and are most easily perceived on the crenate lateral 

 margin. The scutellum is black, ochraceous at the base, and its sides at the apex 

 are marked with ochraceous in a V-li^^e form ; the elytra are in larger part of a dull 

 brick-red colour, feebly depressed along the suture, longitudinally sub-costate along 

 the middle, the costa being broken in front of the middle, and its anterior portion 

 placed nearer the middle than that behind it ; along the suture the colour is black, 

 and on the middle this black colour is expanded to form a quadrate mark, which is 

 divided by a furcate ochraceous mark ; from the posterior part of this there is an 

 extension of the ochraceous colour backwards, the black colour there being thus 

 limited to the raised sutural margin, there is a transverse sub-reniform mark on each 

 side quite close to the apex ; external to the costa there is a black vitta, interrupted 

 by two large ochraceous marks, and some few irregular smaller marks ; the surface 

 18 marked with some undulate transverse aciculations : the pygidium may be either 

 red or black, and the aciculations are more distinct on it than elsewhere. The 

 under-surface is black, marked with transverse patches of a very pallid ochraceous 

 colour. There is only an extremely slight prominence of the mesosternal process. 

 The male has the second, third, and fourth rings of the hind body concave along 

 the middle, and the front tibia acutely bidentate. The female is unknown to me. 



This is a species of considerable interest ; in the first place 

 because the strongly margined unnotched clypeus is a very exceptional 

 character in the genus, and next because of its peculiar resemblance 

 to the female of M. quadriviUata. In this latter species the male is 

 very unlike its female, whereas the male of M. Halyi almost exactly 

 resembles superficially the female of M. quadriviUata ; I am not ac- 

 quainted with the female of M. Halyi, but have little doubt it will 

 be found closely to resemble the male. We have thus a very curious 

 mimetic analogy between the two species, which may be thus briefly 

 stated : I£. Halyi and M. qaadrivittata occur in company, and struc- 

 turally are very distinct species, but the female of the latter simulates 

 the appearance of the former species, though the male of M. quadri- 

 viUata looks very different. I may add that I think it will not be 

 very long before the two insects will be treated as belonging to dis- 

 tinct genera. 



Southampton: Z)eee??iier, ]885. 



