118 THE CANADIAN ENTOMOLOGIST. 



joint ten this number is low, and has no accessory at the upper corner of 

 the spiracle. Anal shield and preceding plates light in colour and of less 

 prominence than in some cases. Spiracles elliptically ringed with black. 

 Length, 27-30 mm., termination of stage July 20th to 25th. 



Last stage : Head darker and less polished, no side line evident ; 

 width, 2.5 mm. Body gains in fullness more than length, colour yellowish- 

 white, the lines lost. Tubercles and plates the same, the former more 

 accentuated as their colour has darkened. Cervical shield preserves its 

 prominence, the darkened lower edges merge together over the anterior 

 portion. Lateral tubercles nearly of one size, iv low on joint 10 ; all are 

 black. Spiracles now black. Length, 32-34 mm. Maturity is reached 

 Aug. 1 st to 6th. Pupa is rather slender, of the normal light chestnut- 

 brown colour, the spiracles slightly darker, spur bifidate. There are no 

 modifications of importance. Dates for emergence, Sept. 12th to 20th. 



Superficially, rigida larva seems most like sciata, and when first 

 encountered was welcomed as differing from the prevalent nitela class, 

 where specific limitations are meagre. Frequently one finds in its com- 

 pany, in the same root cluster, the little Sesia rut Hans, Hy. Edw., which 

 seems fond of the Helianthus generally. Indeed, it must be a very general 

 feeder, from its wide distribution and the number of food-plants already 

 known, and it seems to have an unusual distinction in another direction. 

 If Beutenmuller has the synonymy correct, a description under eight 

 different names in one paper, with a place in two genera, is no mean 

 record for such a little fellow. 



TWO SUBMERGED SPECIES OF GEOMETRID^. 



BY RICHARD F. PEARSAI.L, BROOKLYN, N. Y. 



It is rather curious that the application of our geometrid names should 

 have become so confused. The two instances which, at this time, I seek 

 to correct, concern species comparatively well known. Turning to our 

 List (Dyar, No. 3383), we find Mesoleuca hersiliata, Gutn., with synonym 

 flammifera, Walker. This is correct, so far as it goes, but after complet- 

 ing his description referable to hersiliata, Walker added the following : 

 " Var. B. — Fore wings with the exterior emitting a much shorter tooth 

 toward the discal mark; exterior band quite obsolete hindward, apical black 

 mark much larger, marginal black line divided into pairs of points." In 

 this brief reference he characterizes a species which has never been 

 separated from hersiliata. It is entirely distinct in pattern of markings, 

 and is larger in size, though its colour scheme is much the same. A detailed 

 description follows under the name of 



April, 1909 



