54 C. HERBERT HURST. 



Behind the compound eye, on each side of the head, is an ocellus 

 with fully-developed lens, etc. In the youngest pupse it is separated 

 by a small interval from the compound eye (see Fig. 1) ; but the 

 growth of the latter obliterates this interval, and the ocellus is in 

 the older pupa? not readily distinguishable except in sections. The 

 statement, found in systematic works, that the Tipulariae are devoid 

 of ocelli is, however, not strictly true ; in Culex, at least, they are 

 well developed, though, as they abut upon the compound eye, they 

 are in the imago so inconspicuous that they may easily be over- 

 looked. 



In the mouth-parts, the labrum, epipharynx, mandible, maxillae with 

 their palps, labium and hypo- and epipharynx are present, though 

 the two last can only be seen on dissection. 



Of their mode of origin in the larva I as yet know nothing. At 

 the time of escape of the pupa from the larval cuticle they are 

 of the full size, which is considerably greater than in the adult. 

 The form of most of these parts is shown in Figs. 1 and 2. That I 

 may not have to refer to these parts again, I will at once say that 

 the chief changes which occur in them during pupal life are : — 

 (1) The development of a cuticle within the pupal cuticle, and this, 

 in the case of the labium (fused second maxillae), is covered with 

 scales closely resembling those found in Lepidoptera; (2) a con- 

 siderable shrinking ; (3) in the male only, atrophy of the mandibles, 

 which in a young pupa are as large as in the female, but in the 

 adult are not recognisable. 



The antennce, which were folded and telescoped at their bases in 

 the larva, are in the pupa laid upon the sides of the thorax, as seen 

 in Fig. 2. Their hinder (distal) extremities are hidden by the wings. 

 The swollen basal joint of the antenna of the imago is hardly 

 recognisable on the surface, although it is already a conspicuous 

 object in sections of the youngest pupae, and even in the larval state. 

 I shall describe it with the other sense organs. The shaft of the 

 antenna is segmented, but the external segmentation loses its cor- 

 respondence with the segmentation of the developing antenna 

 within it early in pupal life. 



The thorax is large and rounded, but somewhat compressed from 

 side to side. Mid-dorsally the cuticle of the prothorax is marked by 

 fine transverse corrugations, and this is the part which ruptures to 



