506 Miscellaneous. 



Another very remarkable fact, whicli has not previously been ob- 

 served, is a difference in the number of ganglia in the same species 

 according to the sex. The workers and the females of Bomhus have 

 six abdominal ganglia, while the male has only live ; the working 

 bees have five abdominal ganglia, while the queen and the males 

 have but four ; the male MegaiJille has four abdominal ganglia, 

 while the female has five ; the working wasps have five ganglia, 

 the females and the males six. 



The stomato-gastric system is composed of a frontal ganglion, two 

 ungeian ganglia, two trachean ganglia, and a ventricular ganglion. 



II. Nervous System of the Lnrvoi. — The nervous system of the 

 larvae is very uniform. The larvae have thirteen ganglia, while the 

 caterpillar of the Lej^idoptera has only twelve. The larvae of the 

 Hymenoptera have eight abdominal ganglia, which are all simple ; 

 in very young larvae, however, the suboesophageal and the last abdo- 

 minal ganglia show traces of the fusion of three embrj^onic ganglia. 



III. Nervous System of the Embryo. — The researches of 0. Hietschli 

 and of A. Kowalewski on the development of the bee have proved 

 that the embryos possess seventeen ganglia — ^that is to say, one supra- 

 oesophageal ganglion, three small suboesophageal ganglia (which unite 

 to form a single suboesophageal ganglion in the larva), three thoracic 

 and ten abdominal ganglia (of which the last three form afterwards 

 the last abdominal ganglion of the larva). 



IV-. Metamorphoses of the Nervous System. — The changes which 

 the nervous system undergoes during the metamorphoses of the 

 larva are produced by the fusion of several ganglia. The first 

 thoracic ganglion of the larva remains isolated in the adult insect ; 

 the second and third thoracic ganglia of the larva approach one 

 another more or less, and in some they blend into one medullary 

 mass. The first abdominal ganglion always joins with the last 

 thoracic, so that the adult insect has never more than seven abdo- 

 minal ganglia ; but in most cases the second abdominal ganglion 

 also unites with the last thoracic ganglion. If the number of 

 abdominal ganglia diminishes yet more in the adult insect (5, 4, 3 

 ganglia), this is effected by the fusion of some ganglia with the last 

 abdominal ganglion. — Comptes Bendus, Sept. 18, 187G, p. 613. 



On some remarkable Species of Mantidoe. By Prof. J. Wood-Mason. 



These insects belong to that division of the family in which either 

 the legs or some parts of the body are provided with appendages, and 

 to that section of it in which in males as well as in females the 

 antennae are simple and setaceous and not pectinated ; and I invite 

 attention to some sexual differences presented by them which, I 

 believe, have never before been noticed. 



In Hestias Brunneriana the head of the female is prolonged ver- 

 tically in the form of a cone bilobed at its extremity, while in the 

 opposite sex this great cone is represented by a mere tubercle as in 

 both sexes of the species belonging to the genus Creobrota ; the fore 

 femora, which are wanting in the specimen from which the species was 

 described by Saussure, are equally conspicuous in both sexes, being 

 very broadly oval, with their upper margins very strongly orested. 



