loith descniMons of two new sijecies from Formosa. 363 



(Fig. 7). Ill tlie upper part of this anterior sloping surface is the 

 moutli (Fig. 8c), which in this specimen was covered by a brownish 

 mass (figs. 7a, 8«), apparently of cuticular substance, attached to the 

 surface of the larva by its upper edge as by a hinge. In Fig. 8a 

 it is shown lifted up to expose the mouth aperture. On the ventral 

 surface of this anterior constricted part of the larva, a little behind 

 its front edge, there are in the middle two small flattened pieces 

 with rounded apices (Figs. 76, 8?^), close together and projecting 

 downwards. The skin of the larva bears some fine longitudinal 

 creases in the region of the constriction. 



It is quite uncertain whether the anterior constriction 

 of the larva is merely accidental or not. There is the 

 possibility that the larva was leaving the genital aperture 

 of the adult at the time when the latter was captured, 

 and that at death the abdomen of the adult contracted on 

 the larva, constricting it forcibly. On the other hand, 

 the constriction is extremely regular in its formation, as 

 though it might be natural to the larva. One may quote 

 an observation recorded in an as yet unpublished paper by 

 Mr. F. Muir, who investigated the anatomy of certain 

 Nycteribiids in the island of Larat (Timorlaut Islands). 

 He states that the larva3 had " a constriction at the anterior 

 end cutting off a small mass " ; he speaks of the mouth as 

 being on this small mass, but says that no signs of mouth- 

 organs were visible. I understand from Mr. Muir's paper 

 that this refers to larvae which he found by dissection still 

 in the uteri of the adults. The brownish mass closing the 

 mouth aperture in my specimen is probably no more than 

 a mass of cast skin. But the two small structures (Figs. 

 1h, 8h) appear too regular in form to be in any way 

 accidental. Were it not that they are placed below, and 

 so far away from, the mouth, one might consider them to 

 be rudimentary mouth-organs such as have been described 

 by Leuchart *' and Pratt f in the larva of Melopliarjus 

 ovinus. Such mouth-parts have not been seen in Nycteribiid 

 larvae % previously described. 



For the rest, the larva of P. j'cnynsi agrees with the 

 general description of Nycteribiid larvae given by Speiser. 

 It is yellowish-white (preserved in spirit), slightly flattened 

 dorsoventrally. It has the usual 2 pairs of spiracles 



* Abh. Naturf. Ges. Halle IV, 1858, p. 176 and Taf. 3, Figs. 1, 2. 

 t Arch. Naturg. 59 (1), 1893, pp. 156, 165. 

 i Speiser, Arch. Naturg. 67 (1), 1901, p. 28. 



