THE CANADIAN ENTOMOLOGIST. 183 



before it is colourless), and consisting of three joints. The middle tibia 

 has two brown zones, and a large thick spur. The ovipositor projects 

 but slightly beyond the abdomen, and bears on each side of its tip a small 

 brush of hairs. 



Tachardia gemmifera must, I think, be regarded as an injurious insect, 

 since it affects the Coco Plum rather seriously. The lac is so small in 

 quantity that it would probably not pay to collect and prepare it. 



Institute of Jamaica, Kingston, 

 Jamaica, Dec. 27, 1892. 



NOTES ON TAXONUS NIGRISOMA AND T. DUBITATDS. 



BY J. G. JACK, JAMAICA PLAIN, MASS. 



The following notes of observations of some stages of these two little 

 saw-flies are fragmentary and incomplete, but they are now given as they 

 may be of some assistance to others working upon this group of insects. 



Taxo?ws nigrisoma, Nort, Larva. — The fully grown larva is cylindri- 

 cal, and 10 to 12 millimeters long. It is of a pale green colour above, 

 very slightly darker towards the sides above the spiracles, the spiracle 

 line being marked by very minute dark dots one to each segment ; and 

 the under side (including the abdominal or prop legs) is of a dull whitish 

 colour. 



The upper part of the head is dark brown, shading from pale brown 

 to whitish on the face and whitish beneath. 



The eyes are black and prominent ; antennae small, six-jointed and 

 light brownish coloured • and the mouth parts dark. 



The thoracic legs are of a dull white colour, generally bearing more or 

 less easily distinguishable narrow smoky brown or dark markings on the 

 outer side of the apical segments, the strong, simple, terminal claws 

 usually having a dark brown or black tip. 



When they ceased feeding at full growth the larvae abandoned the 

 leaves of their food plant, which was Polygonum MuJdenbergii, Watson, 

 and prepared for pupating by boring into the green stems of the food 

 plant or sometimes into some such substance as partially decayed wood 

 if it happened to be in the vicinity. In these burrows pupation takes 

 place without the formation of any cocoon. The pupa is uniformly 

 yellowish-white in colour, the dark eyes showing prominently. 



Within a week or two after entering their burrows the insects emerge 

 as saw-flies. Both larvae and pupa? were, very much parasitized by 



