55S lepadtd^:. 



compressed capitulum,but owing to the excessive thinness and 

 flexibility of the whole external membrane, it is difficult to as- 

 certain the relative position of the different parts. Moreover, 

 owing to the pupa being so much flattened, these lobes are 

 necessarily formed folded up; and, I believe, it depends on the 

 position, with respect to surrounding objects, which the male 

 ultimately holds, whether the lobes ever assume, their appa- 

 rently normal position, in a plane at right angles to the sides 

 of the pupa ; owing, also, to the form of the pupa, the two 

 lobes seem generally to be actually formed of unequal sizes, 

 that formed in the dorsal region of the pupa being the largest. 

 I believe that these lobes correspond with the lateral margins 

 of the upper end of the peduncle of the female, which mar- 

 gins project laterally beyond the sides of the capitulum. The 

 lower lobe, or end of the peduncle, is depressed in the same 

 plane with the lobes ; it is of variable length ; when first 

 formed it hardly extends beyond the basal articulation of 

 the prehensile antennas. Commonly it does not lie quite in 

 a straight line of the capitulum ; and I have seen speci- 

 mens in which it stood at nearly right angles to the 

 capitulum and to what was the ventral surface of the pupa ; 

 this irregularity in the relative position and sizes of the 

 different parts of the peduncle, no doubt, to a considerable 

 extent, depends on the form of surface to which the male 

 becomes attached, just in the same way as we have seen 

 that the peduncle of the female becomes altered in shape 

 during the excavation of the chamber in which it is lodged. 



I feel some difficulty on one point : in the pupa the single 

 eye of the future male can be clearly distinguished, and it 

 lies some way from the anterior end of the body; but in two 

 males, which certainly had just moulted, and in which none 

 of the internal organs were as yet developed, the eye lay close 

 to the anterior end, directly over the basal articulation of 

 the antennae. I suspect this is somehow caused by the 

 great change of form which supervenes, during the metamor- 

 phosis, at this anterior end of the body j the extremely com- 

 pressed body of the pupa having to become depressed and 

 lobed in the young male. I have given a figure of a young 

 male, just as it appeared (PL 23, fig. 18), somewhat dis- 

 torted from lying on a flat surface; c, being the eye. 



The sack extends, in a very remarkable manner, down to 



