168 MESSES. C. HOENE AND P. SMITH ON HTMENOPTEEA 



in size and colour, doubtless in consequence of obtaining more or less food in their larva- 

 state. Their sting is very sharp; but they do not attack one when disturbed, but 



fly off. 



Rhynchium brunneum, Fabr. 



This insectin its habits resembles its associate B. carnaticum. It uses holes ready 

 prepared— although, having seen it emerge from a gnawed hole in a soft post, the hole 

 being the work of the insect, I believe it sometimes to work for itself in preparing a 

 habitation. Its body is singularly flexible, so that it is almost impossible to hold it, 

 when alive, without being stung by it. 



Ehynchium mtidulum, Fabr. (Plate XX. figs. 1 & 1 a.) 

 This extremely interesting insect constructs cells of exceeding strength, mostly upon 

 timber. The clay is very finely worked with water and some kind of gum— not only 

 viscid ejection being employed, but also the juices of the "Peepul" {Ficus religiosa), bird- 

 lime in fact, and the gum of the Acacia catechu and other trees. Hence there is no 

 need of thickness, and we accordingly find the walls of the chambers very thin, whilst 

 their tenacity is so great that the portion of the hard wood on which the series of cells 

 was fixed I have cut out with a chisel and hammer without in any way injuring the 

 structure. One pair of insects does not usually make more than three cells ; but it 

 must be remembered that they take a much longer time in making them than does the 

 rapid rough-working Megachile. 



The food stored consists of caterpillars ; and I have not yet succeeded in hatching a 

 parasite from one of their nests, which are strong enough to resist all ordinary attacks. 

 Until completed, either one or the other of the insects appears to remain at home (fig. 1); 

 and hence parasites have no opportunity of efiecting an entrance before the cell is closed 

 over. The covering, though thin, is very tough, so tough that I doubt the power of a 

 parasite to pierce it. In the figure it will be observed that six cells have been built one 

 on another, only one being affixed to the door. This one was attached to a smoothly 

 plane surface of "Sal wood" {Shorea robusta)\ so that the cementing gum must have 

 possessed great strength to allow me to cut it out with a hammer and chisel, as before 

 alluded to. 



These insects build on roof-beams, so that their nests generally escape notice, besides 

 which they are far from common. They are externally of a rich brown colour, glisten- 

 ing with gum. 



Pterochilus pulchellus, Smith. (Plate XXI. figs. 8, 8 a, & 8 J.) 

 This little insect builds its parallel galleries on the nearly smooth surfaces of white- 

 washed and other walls. The cells, as shown in the drawing, are above one another, 

 lined with a gummy substance and fine silk {V) The chrysalis resembles that of Pelopcms, 

 to which, however, the insect is altogether unlike. The clay must necessarily, from the 



