Notices respecting New Books. 137 



development of its >-illous coats are more considerable in the 

 herbivorous animals, on account of the tastelessness of their 

 food, \shereas the jjrehensile organs are more developed in the 

 carnivorous animals. In the same way he observes with respect 

 to the alimentary canal, that the more the animal lives upon 

 vegetables the more extensive is this canal. Thus, according to 

 his observations, the connection between the proportions of the 

 intestinal tube and the species of food is the same in the masti- 

 cating insects as in the animals with vertebras. 



Fully sensii>le of the importance of the determination of all 

 these mimitire to the study of animals in a general point of view, 

 M. de Scrres has lost no opportunity of generalizing the facts 

 which he observed, and always with that rigour wliich the pre- 

 sent state of the sciences demands. The following are the 

 theorems witli whicii he convludes his work : 



" 1. That there do not exist any insects which operate a true 

 rumination ; and that the or f hop tercp, which had been erroneously 

 supposed to ruminate, cannot possibly from their structure 

 throw up their food into their mouth. 



"2. That the gizzard of insects, assimilated improperly to the- 

 bonnet of the ruminating animals, cannot un<!er any circum- 

 stances bring the food up to the stomach, either on account of 

 the arrangement of its valvules, or from the relative weakness of 

 its muscular power when compared with the resistance of it« 

 scaly membrane. 



*' 3. Tliat tlie viscera hitherto considered as third and fourth 

 stomachs are hepatic vessels, or kinds of vesicles wliich serve as 

 a fescrvoir to the biliary fluid ; those organs having, umler cer- 

 tain circumstances, secretory vessels destined to suck up the ma- 

 terials of the humour whicli they are to elaborate, and in other 

 cases operating of themsebcs the secretion for which th.ey are 

 destined. 



" 4. That in the vcrv voracious species there are several orders 

 cr rows of hepatic vessels, and in those which have the most, 

 the number of rows of these ves'cls never exceedt. three. 



" 5. Til at the upper hepatic vessels are always more developed 

 than the lower, and their extent in the inverse ratio of their 

 number. 



" G. That when there is only a single order of hepatic vessels, 

 these vessels are merclv simple elongated tubes, almost capillary, 

 and floating freely in the interior of the body. 



" 7. That the development of the hepatic vessels is always re-, 

 lative to the extent and complication of the gizzard ; these two 

 kinds of organs being themselves in proportion with the quantity 

 and species of food us^ed by the insects. 



"S. That 



