HYLOICUS PINASTRI. 289 



area was raised, with a definite sulcus round its anterior border. 

 Few specimens are quite without, and one or two have, very markedly, 

 a deep little pit at the outer margin of the propedal scar, this has 

 nothing to do with the scar, as, in the specimens which show it 

 best, it also occurs on segment 7. It probably represents the triple- 

 haired tubercles that occur here in the larva. The scar of the 

 larval horn may be merely a small smooth area, more usually it 

 is a definite little rounded raised protuberance smoother than its 

 surroundings and with a slight hollow behind it. The anal spike is 

 2"omm. to 2"6mm. long, and about i^mm. in diameter at the base, 

 not narrowing so rapidly towards the base as apically, but varying 

 much in this as in other particulars. An odd specimen is found 

 with the spike almost identical with that of S. ligustri (which varies 

 less), but most have the lateral points nearer the end and smaller, 

 others have them nearly obsolete, one or two have them larger, 

 or with several irregularly placed ; the end is bifid, basally it is 

 wrinkled coarsely, as coarseness goes in this pupa. Anterior to 

 the spiracles and thence dorsally for a length of about 4'omm., there 

 is, on the anterior margin of segments 5, 6 and 7, a quite smooth 

 surface margined by rather sharp raised ridges, the posterior being 

 the Sphingid prespiracular flange, and a third slight ridge can be barely 

 seen, deep in the incision, when the segment is well bent to the 

 other side. The anal scar is a longitudinal impression about i^mm. 

 in length, often narrow in front, wide behind, and, usually, with raised 

 margins. The male tubercles are two raised smooth eminences 

 with a depression between them and enclosed by a circular (or 

 nearly so, it is usually a little wider transversely) groove. They 

 occupy nearly the whole width, but rather encroach on the 

 posterior, avoiding the anterior, margin of the 9th segment. The 

 incision in front, however, is smoothed out to about the same 

 degree as that behind. In the female, these incisions are still 

 more smoothed out, but have little of the usual appearance of 

 the posterior segments having been drawn forwards into the anterior. 

 There is a round pore in the middle of the 8th segment, but with 

 the appearance of really belonging to the 9th, and another half-way 

 between this and the anterior margin of the segment, the latter being 

 continued as a narrow slit to the anterior margin of the segment. 

 In another specimen (one only) both these pores are united in a 

 deep, wide impression, extending from the middle of the segment 

 to its anterior border. In another, both are very distinct and 

 separated ; the anterior one is in the middle of the segment, the other 

 behind it, the slit extending to the anterior margin of the segment 

 is a mere faint line and does not extend to the pore. In another, 

 the two pores are conjoined, but distinct from the faint line extending 

 to the anterior margin of the segment. The first and third of these 

 varieties are the more numerous. The microscopic aspect of the 

 pupa shows the pits to be pale with shading radiating from the 

 centre to the irregular margins. In showing the transition from 

 pits to wrinkling, the 8th abdominal segment is most instructive. 

 From the pits radiate, generally laterally, one, two, or more of the 

 fine dendritic lines that mark the bottoms of the sulci between 

 the wrinklings, and, when they are numerous, present a similar 

 pattern to nerve cells with their dendritic branchings. Hairs are 



