Mar 1399] Fall: On American Species of Acm^odera. 21 



A. labyrinthica, sp. nov. 



This name is proposed for a form which is indiscriminately mixed 

 with connexa and acuta, according to the size of the specimens or the 

 taste of the individual. It may usually be separated at a glance from 

 both by its stouter form and the more profuse and irregular markings 

 of the elytra. Like connexa the form is strongly depressed, but is less 

 gradually narrowed posteriorly and with more distinct bronze lustre. 

 The thorax in connexa is usually conspicuously wider than the elytra 

 and widest immediately before the base ; in labyrinthica the thorax is 

 less noticeably though usually slightly wider than the elytra with the 

 broadest part a little less basal and with a more evident sinuation be- 

 fore the hind angles which are consequently a little less obtuse. The 

 abdominal punctuation is a little less fine in labyrinthica, the last 

 ventral shorter with the apical carina often very small, but rarely lack- 

 ing. From acuta, labyrinthica differs by the flatter form and much 

 coarser strial punctures. In both there is rarely a small yellow spot 

 at the side of the thorax, but I have never seen this in connexa. In 

 many specimens of labyrinthica the last ventral suture is broadly feebly 

 sinuate or subangulate at the middle : not noticeably so in acuta or 

 connexa in my experience. 



Typical connexa, labyrinthica and acuta, and even after allowing 

 for a considerable variation the great majority of specimens are such, 

 are easily separable, but there are not lacking specimens which are 

 very disconcerting. It is possible that these are only additional forms 

 which indicate a single excessively variable species ; it is, however, 

 quite as likely that they are representatives of still other closely allied 

 species and, perhaps, still more probable that we have to do with a 

 complex combination of completely and incompletely differentiated 

 forms which the presence of hybrids may render still more confusing. 

 Whatever may be the true status, the separation of labyrinthica, either 

 as a species or a subspecies, goes far toward relieving our series of 

 connexa and acuta of that heterogeneous appearance which is nowhere 

 better illustrated than in the Leconte and Horn collections. Length, 

 7.5-10.5 mm., .30-.42 inch. 



Habitat: Inhabits nearly the same region in California as acuta, 

 though I have not seen specimens from quite so far north, and also 

 extends its range into Nevada and Utah. 



A. cuneata, sp. nov. 



Depressed, strongly narrowed behind. Head rather deeply, broadly impressed. 



