PHASMIDAE 



263 



of crop and proventriculus, but the true stomach appears to consist 

 of two different parts, the anterior being remarl^ably uneven 

 externally, tliougli destitute of coeca, while on the posterior part 

 there are peculiar vermiform processes. There are eighteen or 

 twenty tubes in each ovary. 



When the young Insect is in the egg, ready for emergence, 

 the meso- and me ta- thorax are not remarkably elongate, so that 

 the femora are not very far 

 apart, but by the time the crea- 

 ture has fairly emerged from the 

 prison of its embryonic life the 

 thoracic segments have attained 

 their usual proportions ; much 

 expansion of the body takes place 

 as the Insect leaves the egg, so 

 that it appears a marvel how it 

 could have been contained therein ; 

 this expansion affects the parts 

 of the body unequally. 



The records as to the post- 

 embryonic development of Phas- 

 midae are very scanty, but indi- 

 cate great differences in the 

 length of time occupied by it. 

 Bacillus jpatellifer is said to 

 moult several times, Biajiliero- 

 mera fcmorata only twice. This 

 latter species becomes full grown 

 in six weeks, while, according 

 to Murray,-'- Phylliuni scythe 

 required fifteen or sixteen months for growth, and did not 

 moult until ten months after hatching ; the number of 

 ecdyses in the case of the Phyllium was three. At each 

 change of skin an immediate increase in size, similar to that we 

 have noticed as occurring on leaving the egg, takes place ; each 

 limb on being freed becoming about a fourth longer and larger 

 than the corresponding part of the envelope from which it has 

 just been withdrawn. After the second moult of Phylliuvi the 

 tegmina and wings made their appearance, but remained of very 



' Edinlurgh Philosoph, Joxirn. January 1856. 



Fig. 1.50. — Ascliipasma caiadromus, female. 

 Sumatra. Natural size. (After West- 

 wood.) 



