72 Mr. S. Maulik on Variation in the Prothoracic 



I have observed that of the pair of frontal spines, one con- 

 sists of two spines and the other three. This, of course, is 

 abnormal. There is no correspondence between the number 

 of the frontal spines and the lateral ones. Each of the 

 frontal pair may consist of two (fig. 1) or three, while the 

 lateral group may be composed of four, three, or even two. 



Variation of the Lateral Group of Spines. 



The usual number is four, as is seen in the majority of 

 specimens before me. They may be three, or even two, as 

 L)r. Gestro has already pointed out in a little note. In one 

 individual before me the group on the left side of the pro- 

 thorax consists of three spines, while on the right there are 

 three, with the first one having a little appendix arising from 

 its front margin (fig. 5). The spines are slightlj r inclined 

 outwardly to the vertical line, the front i. e., one nearest the 

 head is smaller than the second which follows it. The latter 

 is inclined to be the longest, sometimes it is a little curved. 

 The third is slightly shorter than the second. The fourth is 

 always shorter than others ; it is sometimes quite close to the 

 third, but occasionally it may be considered as standing 

 apart (fig. 7). For purposes of classification I should con- 

 sider this group as consisting of four spines having a common 

 broad base. Jt may be observed here that the individual 

 having a lateral group of three spines has the basal joints of 

 the antennae ferruginous and has a fine longitudinal impres- 

 sion along the middle line. The whitish hairs on the surface 

 of the prothorax are also more prominent. These characters 

 are not seen in the examples having a lateral group of four 

 spines. 



From the above considerations it will be seen that the type- 

 specimen at Budapest Museum from which the first descrip- 

 tion was drawn up is not typical of the species ; it is only an 

 aberration. The normal form is one with a lateral group of 

 four spines. There are specimens of the normal form in the 

 British Museum, in the Genoa Museum, and in the Indian 

 Museum, Calcutta. 



Description of the Insect. 



Body elongate, with a little constriction in the middle. 

 The colour is shining black, specially on the elytra. The 

 mouth-parts, the antennae, the abdominal segments, and. the 

 legs are yellow. The antennae are slender, with the apical 



