a carnivorous Tipulid larva. 253 
Fig. 22.—Do., in longitudinal section. f, fold of epithelium 
surrounding the mouth of the spiracle. x 100. 
Frc. 23.—Surface view of spiracle. x 100. 
Fic. 24.—Fore part of body, showing part of retracted head, h; 
the brain, b, and anterior ganglia, the salivary glands, sg, and 
their ducts, and the trachee. x 20. 
Fic. 25.—Hind part of body, showing the trachew distributed to 
the branchial appendages and their connection with the spiracles. 
x 20. 
Fic. 26.—Posterior end of dorsal vessel and pericardium from 
beneath. ‘The elliptical ventral opening, vo, in the pericardial 
wall is seen towards the bottom of the figure. Upon the inner 
outline, which is that of the heart, can be seen the terminal inlet, 
with its pocket valves, pv, and further forward a constriction, 
which possibly conceals a pair of ostia. The spiracles and longi- 
tudinal tracheal trunks appear on each side of the pericardium ; 
al, alary muscle. x 50. 
Fic. 27.—Part of fore end of dorsal vessel, with pericardial cells 
attached. x 100. 
PLATE XIII. 
Fic. 28.—Dorsal vessel and pericardium, general view. br, brain. 
x 8. 
Fic. 29.—Do., in side view, with outline of body, x 8. The peri- 
cardium is seen to be attached to the intestine at the point a. 
Fic. 30.—Nervous system of larva. The head is considerably 
retracted. x 5. 
Fic. 31.—Part of ovary of female larva in longitudinal section, 
showing the multinucleate follicles of the ova. od, oviduct. 
x 3850. 
Fia. 832.—Pupa, side view. The dorsal abdominal plates should 
all be shifted one segment further back. They are actually carried 
on the same segments as the pseudopods. x 6. 
Fic. 85.—Pupa, ventral view. xX 6. 
Fic. 34.—Respiratory trumpet of pupa, in section. At @ the 
pores for admission of air are shown in surface view. 50. 
Fig. 35.— Transverse section through respiratory trumpet, 
passing through a pore (diagrammatic). The cuticle and tracheal 
lining are detached, except in the neighbourhood of the pores. 
