42 Bulletm of the Bro'oklyn Entomological Society Vol. XV 



thorax and the basal and apical parts of the elytra, and the median 

 markings of the elytra always follow the suture to about the 

 middle then turn at right angles. The elytra are also proportion- 

 ally narrower and the apices more distinctly pointed. In undu- 

 latus, the design, whether complete or not, is always more sharply 

 defined against its background, there is an absence of that diffuse 

 sprinkling of colored hairs over the surface, and the markings 

 along the suture diverge considerably from it as they proceed 

 backwards. At one time I was inclined to consider cinereus as 

 but a western race of X. fusciis Kirby, a species which has been 

 proven by Mr. C. A. Frost to feed on the true fir and as stated by 

 Col. Casey^ is quite distinct from undulatus. The color pattern 

 of fuscus, is, however, quite dififerent from that possessed by 

 either undulatus or cinereus, the elytral markings in fresh and 

 fully colored individuals consisting of a series of long and an- 

 gular loops. In cinereus, the scutellum is always densely clothed 

 with white hair while in the other two species, it is almost uni- 

 versally naked. 



Xylotrechus insignis Lee. 



This species is not only one of the most elegant in the genus 

 but is remarkable in having the sexes so differently colored. It 

 is widely distributed throughout California and runs well into 

 Southern Oregon. The females which are black with rufo- 

 castaneous antennae and legs and variously barred with sharply 

 defined yellow markings above, vary somewhat as to size and as to 

 the breadth of the yellow markings, but as a whole may be con- 

 sidered to be fairly constant. The males, however, vary consid- 

 erably. The typical male is rufous with the prothorax generally 

 slightly margined with yellow both apically and basally, with a 

 crescentic yellow patch transversely crossing the scutellum, a 

 short yellow bar running inwards from the humeri, a transverse 

 bar placed entirely across the elytra one third distant from the 

 apex and a small poorly defined patch at the apex. This is the 

 form which is generally to be found distributed throughout the 

 middle portion of California and the Sierras. One specimen 

 which I have seen from San Diego, is like the preceding, but with 



1 " Memoirs on the Coleoptera," III (1912), by Thos. L. Casey, p. 359. 



