50 



The shot-holes associated with Thripsidas* are markedly different 

 under these tests from those of the cases where the holes are the result 

 of attacks of fungi. In the latter cases it is a matter of comparative 

 ease to demonstrate the. presence of the fungus causing the disease. 



* NOTE. In order to leave no doubt as to the species under observation, the following ana- 

 tomical notes are added. Other species were occasionally seen in stone-fruit buds, usually 

 mature insects such as the commonest rose thrips, but this occurrence was only occasional, 

 and not to be wondered at, for the season was marked by the abundance of thripsidae on the 

 rose and a number of other plants, and, in consequence, stray insects of this sort were to be 

 found in almost any situation. For example, one day in the middle of the city of Sydney, 

 at a distance of nearly 150 feet from the ground, namely, at the top of one of the tallest 

 buildings, it was possible to see these little insects at nearly every instant by keeping a 

 sharp look-out against any dark object or shadow. The bright motes to be seen in such 

 abundance, moving through the sunshine, were full-yrown thrips of both sexes, and, of 

 course, they alighted, and were to be found, in all sorts of odd situations. 



The largest specimens of the larva found inhabiting stone-fruit buds as described in the 

 preceding pages were about one millimetre long on the 1st of November, and presented 

 anatomical features as follows : 



The head, about as long as wide, was not set off by a very distinct constriction. The 

 small, but prominent, red eyes consisted of some half dozen facets each, a much smaller 

 number than in most species of Thrips. 



The antenna were of about the same length and average diameter as the front legs, and 

 though apparently consisting of only four joints, were really made up of more than that 

 number. The first joint, destitute of bristles, was the widest and shortest of the four 

 prominent sections. The oblong second joint was a little narrower than the first, and 

 one and a half times as long, and bore one row of bristles. The spindle-shaped third 

 joint, bearing one row of bristles, was as long as the first and second taken together, and 

 appeared denticulate in optical section. The mobility of the antenna is largely deter- 

 mined by the structure of this section, which is attached by a narrow and exceedingly 

 short stem. The fourth joint was manifestly compound, ver}^ likely four-fold, and was 

 lanceolate in contour and denticulate in optical section. It was blunt at the apex, as 

 wide as the third, and nearly as long as the first three joints taken together. Taken 

 altogether, it bore several ro\vs of bristles on the distal half. 



The conical nozzle was ordinarily so held as to terminate between the first pair of 

 coxae. Of the two pairs of palpi, one was composed of three cylindrical joints disposed 

 like those of a short open three-fold sliding telescope, the whole being about as long as 

 the front leg was wide, while the second pair of palpi were apparently two-jointed. 



The thorax was two-thirds as long as the abdomen. The only prominent pair of 

 spiracles was on the mesothorax, and appeared as a papilla half-way between the front 

 and middle legs. The prothorax was smaller than the other two divisions, and was set 

 off from them by a slight constriction. In form and size the mesothorax was much like 

 the prothorax. The metathorax was much like the other two divisions, especially the 

 middle division ; it was seen to bear a pair of inconspicuous spiracles. 



The oblate coxae of the front legs were half as wide as the head, and were darker than 

 the other joints. Each trochanter was half as long as the corresponding coxa. The 

 femur and tibia were much alike in form, though the tibia was the smaller and more 

 tapering ; each was about as long as the terminal compound section of the antenna. 

 Both tibia and femur bore scattered hairs, the former having a circlet of them near the 

 middle and at the distal extremity. The tarsvis was composed of two very short, almost 

 naked joints, supplied with a clawless terminal pad. The middle legs, though a little 

 smaller than the front ones, were in most respects like them. The coxas were half as 

 large as those of the front legs, and it was difficult to make out the nature of the 

 trochanter, which was perhaps consolidated with the coxa. The hind legs were a trifle 

 larger than the middle legs, but otherwise were very much like them. 



The thirteen-segmented abdomen was denticulate in contour, and bore twelve hairs 

 on each segment, the hairs increasing rather regularly in length from front to back, being 

 very short on the anterior segments ; but the eleventh, twelfth, and thirteenth segments 

 bore particularly long hairs. Beyond the features mentioned in connection with the 

 thorax, nothing was observed of the tracheal system. 



Habitat. Found in the growing points of the apricot and peach in October and 

 November in the vicinity of Sydney, N.S.W. From one to six individuals were found 

 in each bud, were they lived at the expense of the young growth, determining the 

 appearance at a later date of so-called " shot-holes " in the leaves. These larvae are 

 rather active in their movements, but less so than most species of Thrips. 



