72 Records; of i/tc Indian Mn^ctnn. | Vol. XIV, 



enclosed in a fjlobule of jelly about the size of a small shot. The globule 

 adhered to the case of a larvae, which tried to eat them, but was pre- 

 vented by the jelly from doing so. 



The larva preserved in spirit is of a creamy colour when taken out 

 of its tube ; when alive it was semi-transparent without any tinge of red. 

 It is 6-5 mm. in length, and like the ordinary Chironomid larvge is worm- 

 like in appearance. It differs from the common blood-worms in having 

 no ventral blood-gills on the eleventh segment, and in that the blood 

 lacks red pigment. In one specimen, which was ready for pupation 

 when preserved, the nymphal characters are well developed and can be 

 easily seen in a Canada balsam preparation. It shows that in the nymph, 

 instead of the two groups of respiratory filaments on the pro-thorax, 

 two nymphal trumpets are developed for respiration. The larva is thus 

 of Meinert's Motitor group of Chironomus larvse (6), but differs from 

 other described larvae of this group in having a small head, and in that 

 the brain lies in the pro thorax instead of the head. 



In the body of a young larva the head and the twelve segments 

 of the thorax and abdomen can be easily distinguished (fig. 1). In 

 advanced larvse, however, fusion takes place in the thoracic region 

 and the segments are not easy to distinguish. 



Head.' — The head is a very small structure with a chitinous covering 

 much thicker than that of the rest of the body. It is of a yellowish 

 colour. In front of the antennse it is much narrower than behind. The 

 dorsal surface is very convex, descending rapidly to the nearly straight 

 posterior surface, gradually at the outwardly bulging sides, and with 

 a very steep forward slope on the anterior surface (fig. 3). The 

 ventral surface is nearly flat. The dorso-lateral sides of the head 

 are formed by three chitinous pieces, viz., a median process (the 

 clypeus), and two lateral plates. The lateral plates are designated 

 the epicranial plates by Miall and Hammond (7). This, however, 

 is an inappropriate name when applied to the head of this larva, 

 because in it the brain does not lie in the head, and so this part of the 

 head is not the cranium in a strict sense. The lateral plates besides 

 forming the sides also form a little of the dorsal surface, and are 

 continued ventrally to meet each other in the middle line, where 

 a faint suture can be distinguished (fig. 4). From the anterior margin 

 of the pre-antennal portion of the head a shelf-like fold hangs 

 forwards. Its dorsal surface is convex and highly chitinized. The 

 ventral surface slopes sharply inwards and slightly upwards towards 

 the entrance to the buccal cavity. The ventral surface of this pre- 

 antennal shelf is termed the labrum (la) by Miall and Hammond. It 

 overhangs the mouth-parts, is mobile and can be bent backwards and 

 inwards. On the dorsal surface the shelf bears two setae, one on either 

 side, while on the ventral surface {i.e., the labrum) there are two simple 

 setae in the middle line, and two groups of thick seta3 ; besides these 

 the chitin on this surface is thickened along two crescentic lines on the 

 sides and a central triangular area. The margins of this triangular 

 area are raised into tooth-like processes. 



Ventrally the pre-antennal portion of the head is marked off from the 

 post-antennal by a narrow linear band of thickened chitin arising from 



