156 Records of flic Indian Mtisciim. [Vol. XY, 



the openings as there are in other CuHcidae ; and the gradual closing 

 of the openings of the trumpets seems to have been evolved as a direct 

 response to the surroundings in which these pupae are found. In cap- 

 tivity the adults were hatched only late at night and no observations 

 were therefore made on the manner in which they rose to the surface. 

 The pupa (fig. 6) is easily distinguished by the very long abdomen, and 

 the comparatively small cephalo-thoracic mass, the peculiar breathing 

 trumpets and the well-developed tail-fins. 



The pupa is 6-9 mm. long, and the size of the cephalo-thoracic mass is 

 2-1 mm. by 1-7 mm. 



In the cephalo-thoracic mass of the advanced pupae the large com- 

 pound eye of each side with the single ocellus behind it and the antennae 

 can be distinguished. The legs, the wing and the halter of each side 

 can also be seen in their envelopes. Near the upper edge, arising from 

 the dorso-lateral margins, a single seta is present on each of the pro-, 

 meso- and metathoracic regions. The nymphal breathing trum/pets 

 are large swollen structures appearing baloon-shaped in the living pupae. 

 They are broadest in the middle gradually narrowing to the point of 

 attachment. The wall of the trumpet is formed of small quadrilateral 

 areas. The outer openings are very mimite slits on the upper margin. 



In the abdominal portion, the segments regularly increase in length 

 from the thorax onwards, except for the last one, which is very small. 

 Dorsally each segment bears two setae one on each side, and there is a 

 similar arrangement ventrally. From the last segment two triangular 

 flaps hang out below the tail-fins. The tail-fins (fig. 7) are large, broad 

 structures with a very thick inner margin owing to a tracheal tube 

 running along the edge ; this edge is setose ; the outer edge is thinner 

 and has no setae ; in the substance of the tail-fins of each side four other 

 thickenings due to tracheal tubes can be distinguished. 



Larva of Dixa Montana. 



The larvae were collected in mountain streams at Kasauli in the 

 Western Himalayas. 



Full-grown larvae (fig. 8) measure about 9 mm. in length, smaller 

 ones from 3 — 6 mm. are also present in the collection. The general colour 

 of the preserved specimens is brownish-black alternating with paler 

 areas on the dorsal surface, while the ventral surface is light yellow. 

 The head and the tail-fins are dark brown. 



The head is a small but massive structure formed of thick chitin. 

 The post-antennal portion is quadrilateral, the anterior pre-antennal, 

 which is much darker in colour, being triangular with the apex rounded 

 off. The eyes are rather small, ovoidal, situated ventro-laterally behind 

 the point of insertion of the antennae. The antennae (fig. 9) are slightly 

 curved single- jointed structures about two-thirds of the length of the 

 head, with the shaft and tip covered with closely-set minute spines. 



Month-j)arfs. — The pre-antennal portion of the head ends in the 

 large labrum which, with its very well developed pair of feeding brushes, 

 overhangs the mouth-opening. The mandibles (fig. 10) are large and 

 elaborate in structure ; from the outer angle of the upper margin arises 



