98 Larval ami Pupal Stafjts of Bibiu Johaiiuis' L. 



ventral surface. The spiracles of the twelfth segment are situated half- 

 way between the lateral processes of the dorsal row, and the front of the 

 segment, and they project twice as much as the preceding spiracles 

 ( Plate II. fig. 4). These spiracles have each two openings, while the other 

 spiracles have only one. 



The body is covered by a tough cuticle which is actually of a light 

 brown colour, but the larva appears darker owing to particles of soil 

 adhering to it. and to the dark contents of the alimentary canal. The 

 cuticle bears small irregular shaped scale-like structures, which do not 

 touch one another. These structures are of various sizes, and the 

 larger ones are rather conical and bear from one to eight short and 

 usually backwardly directed spines (Plate II, figs. 7 and S). On the 

 bases of the processes, and on the spiracles of the larva, these structures 

 are closer together and give a more scale-like appearance, while on the 

 processes the spines become considerably longer than elsewhere. 



Each intersegmental region bears a row of depressions which vary 

 considerably in shape. They are placed side by side (Plate II, fig. 6) 

 and apparently similar structures are situated, often singly, on other 

 parts of the segments. These depressions are of a darker colour than 

 other parts of the cuticle, and are surrounded by elongated spineless 

 scale-like structures. 



On the twelfth segment the scale-like structures form a closer cover- 

 ing, which has rather the appearance of a squamous epithehum. The 

 spines of the scale-like structures on the dorsal surface of this segment 

 are very much reduced or absent, except on the processes, while on the 

 ventral surface a single stouter spine is present on each scale. 



From the end of the twelfth segment the larva can protrude pseudo- 

 podium-like structures similar to those of the newly hatched larva, but 

 at this stage they are relatively smaller. 



(h) Internal structure. The Integument consists of a chitinous 

 cuticle, with the hypodermis or chitosrenous layer underlying it. 



The Cuticle consists of two layers, of which the outer is considerably 

 the thinner, is of a light yellow colour in sections, and is highly refractive, 

 except in the head, where the outer layer is of greater thickness than 

 elsewhere, and is of a brownish yellow colour in sections. The inner 

 layer, which is relatively thick, appears to be only partially chitinised 

 and is more readily stainable than the outer. 



The Hypodermis appears to be an imdifferentiated stratum of proto- 

 plasm containing scattered oval nuclei which are hard to distinguish, 

 no cell wall being distinguishable. Below the hvpodermis and in contact 



