34 



THE LARVA OF THE BLOW-FLY. 



head as the first ; Schiner [11], as we have seen, gives thirteen 

 as the general number in the dipterous larva. Weismann 

 apparently overlooked a very obvious segment, between the 

 head and the first thoracic segment. This is usually invagi- 

 nated within the first thoracic segment, so that it cannot be 

 seen except when the larva is forcibly extended ; but New- 



-e c 



Fig. 4.— The Adult Larva of the Blow-Fly. a, Lateral view ; b and C, the head of 

 the same in extension and flexion — li, the great hooks ; si, the stomal disc ; 

 mx, the maxilla ; /, the forehead ; a s/>, the anterior fan-like spiracle, with two 

 lenticular bodies in front of it ; d, the posterior extremity of the same : e, the 

 last two segments, showing liie anus (a) flanked by a pair of false feet. The sub- 

 semicircular plate in front of the anus is the ventral plate of the anal {I5lh) 

 segment. 



port [9] correctly described it. I shall speak of it as Newport's 

 segment. Brauer [14], like Weismann, gives twelve, but 

 believes— and I think correctly— that the last segment is a 

 complex of two. 



