04 



strengthen the terminal claw-joint, was of a very small size, and was generally sol- 

 dered to the base of the claw-joint. Here, then, could be no doubt that ihe fourth 

 joint was becoming, as it were, obliterated ; so that it would be easy to conceive a 

 pseudoletramerous insect in which the soldering of the two terminal joints had be- 

 come so close that all trace of the articulation would be lost ; and if this occurred 

 simultaneously wilh the narrowing of the basal joints we should have before us the 

 hind-foot of a heteromerous insect. The insect under examination presented a dif- 

 ferent mode of the gradual top of a joint. The tarsi consisted of a short joint, rather 

 swollen at the base of the foot, having several bristles placed obliquely at its extremity 

 beneath. This is followed by a long, simple joint, obliquely truncated at its tip, with 

 several bristles inserted obliquely at its extremity beneath, and having a very indis- 

 tinct trace of articulation across the middle; it is nevertheless, however, furnished on 

 the under side, at the point where this central articulation should take place, with one 

 or two fine bristles, like those at the extremity of the basal joint. There then follows 

 a small but distinct joint, at the end of which the long claw-joint is fixed. Here, 

 therefore, the apparent loss in the number of joints was caused by the soldering toge- 

 ther of the second and third normal joints. In its general form, and the nnirj^er of 

 joints and form of the antennae, the insect is closely allied to the genus Orthoperus ; 

 there are, however, certain modifications of structure in the palpi which require fur- 

 ther examination before we can definitely refer the insect to that genus. It was, how- 

 ever, important to determine what bearing this structure of the tarsi would have upon 

 that of the genus Orthoperus, more especially since it was from various observations 

 on this part of the structure of that genus that it had been regarded as a separate ge- 

 nus by Heer, who had named it Pithophilus, and by Redtenbacher, who called it 

 Microsphaera. On examining some specimens of the legs of the common British spe- 

 cies of Orthoperus, mounted in Canada balsam by Mr. VVollaston, we found the same 

 general proportion of the joints; but the articulation between the short basal joint and 

 the long second joint was almost lost; whilst the almost obsolete aiticulalion in the 

 middle of the long second joint, in ihe Madeira species, was quite distinct, the two 

 terminal joints being alike in both. Although, however, the basal joint appeared lost 

 by coalition with the second joint, there still remained evidence of its existence, in the 

 presence of a small, oblique bristle on the under side of the foot, just where the ex- 

 tremity of the basal joint might be looked for. The two structures, therefore, illus- 

 trated each other, proving that these insects, and also leading to the belief thai many 

 other anomalous and supposed tetramerous beetles, are in truth pentamerous insects 

 disguised by the soldering together of two of the adjacent joints of ihe tarsi. 



Mr. Waterhouse said that in some Coleoptera he had frequently observed bristles, 

 such as Mr. Westwood had spoken of, in the middle of an articulation, more espe- 

 cially of the claw-joint in Homalota ; and that therefore the presence of a bristle must 

 not be taken as a certain indication of the existence of a joint. 



Mr, Wollaston said that the bristles alluded to by Mr. Waterhouse, which oc- 

 curred iu the middle of the articulalious, were very difl"erent from those at the joints. 

 A moderate magnifying power would at once show the diiference. 



Effects of the Sting of a Scorpion. 



Mr. Westwood communicated an extract from a letter of a correspondent in India 

 relative to the effects of a sling of a scorpion. It is described as very severe, resem- 

 bling the pain of a dozen wasp-slings concentrated in the same sjiot. The finger 



