42 Proceedings of the 



time the antennse hear the female stamp), I assume that this is 

 the normal character at this period. The form of the segments 

 of the abdomen are somewhat different. They taper to the tail 

 from the third segment, instead of running parallel to each 

 other, or nearly so, throughout the fourth, fifth, and sixth seg- 

 ments. There exist the same number of segments in the ab- 

 domen, and also of parts in the thorax ; but when the wings 

 afterwards appear, there is, of course, some difference. In 

 some specimens I think I can see a swelling where the joint 

 of the wing is to emerge ; and there is a pinching up of the 

 skin where the scutellum afterwards appears, for it is wanting 

 in the young insect, though present in the full-grown one. 

 As already mentioned, the sexual organs are not developed 

 in the young specimen. 



The leaf-insect is subject to three moults, as is generally the 

 case with the Orthoptera. The insect reared by Mr M'Nab 

 was hatched in the beginning of June 1854. Its first moult 

 took place about ten months afterwards, viz., on 10th April 

 1855. During that time it had increased very gradually but 

 not greatly in size. It was not an inch in length when hatched, 

 and at its first moult it measured not much more than an inch. 

 On this moult taking place, the change in its form and propor- 

 tions was very trifling. The abdomen became relatively broader, 

 and the swelling at the part where the wings afterwards burst 

 out more decided. The most interesting change, however, was 

 observed on the antennae ; and, as the circumstance has not 

 hitherto been noticed, it is worthy of attention. A reference 

 to the figure of the female antennse will show that they are 

 short and thick (scarcely one-eighth of an inch in length), 

 and composed of nine joints, the third of which is considerably 

 thicker, longer, and more bulky than the rest. On the other 

 hand, the antennse of the male are long and thin, about one and 

 a quarter inch in length, and composed of twenty-four joints, 

 and the third joint at the base is not thicker or larger than 

 the rest ; on the contrary, the joints get shorter and shorter 

 as they approach the base, and the basal thirteen are de- 

 cidedly smaller, and of a different form from the apical eleven. 

 But the antennse of all the young freshly-eciosed insects 



