the genus Criocephalus. 161 



This very distinct species cannot be mistaken for any 

 other, the structure of the antennae being very peculiar. 

 The terminal four joints are abruptly shorter than the pre- 

 ceding, the eighth joint being scarcely half as long as the 

 sixth. There is not much difference between the sexes. 

 The male has the legs and antennae rather thicker and the 

 terminal joints of the latter not quite so abbreviate. The 

 bush of hair on the gular area is very remarkable in this 

 species. And the clypeus is considerably larger than in 

 any other species ; in this last character it approaches the 

 genus Megasemum. 



Apparently common in N.W. North America ; it ex- 

 tends at any rate from Montana in the north of the United 

 States to Guaymas in Northern Mexico (Matheio). 



Larv/E. 



We have found larvae of at least three species of Longi- 

 corn Coleoptera in the wood of the Scotch fir-trees in the 

 New Forest, viz. Bhagium hifasciatum, Asemum striatum 

 and Criocephalus ferus. These three larvae are extremely 

 similar. The characters of the three forms have been 

 described by Schiodte, so that it is only necessary here to 

 give diagnostic characters. Schiodte and the other writers 

 on the subject have given no information as to the habits 

 of the three larvae, and as these exhibit very striking 

 differences, Mr. Smith's notes on this subject will doubtless 

 be acceptable to a wide circle of entomologists. 



The three larva?, as already stated, are of three different 

 genera, Asemum, Criocephalus and Bhagium. Mr. Smith 

 has never met with all three contemporaneously associated, 

 but Asemum is frequently found in the same stumps as 

 Bhagium ; and in the trees in which Criocephalus has been 

 found in this country it is also associated with Asemum. 



Notwithstanding the extreme resemblance of the three 

 larvae, they may be readily distinguished by the spines at 

 the anal extremity of the body. In Bhagium there is 

 only one spine (Plate IX, fig. 9); in Asemum there are 

 two spines placed near one another ""and divergent (Plate 

 IX, fig. 8) ; in Criocephalus there are two spines placed 

 at a little distance from one another (Plate IX, fig. 7) 

 and parallel, or even at the tips very slightly convergent. 

 In profile the two Asemum spines are i straight ; in 

 Criocephalus they are slightly directed upwards. 



TRANS. ENT. SOC. LONP. 1905.— PART I. - (MAY) 11 



