INSECTA. 117 



More success is to be anticipated from au undertaking which has been 

 commenced on the Continent, by the multifarious and happy activity of 

 Agassiz, and in which he is supported by a considerable number of European 

 Zoologists: 'Nomenclator Zoologicus, contineus nomiua systematica generum 

 Auimalium tani viveutium quam fossilium secundum ordiuem alpliabeticum 

 disposita, adjectis autoribus, libris in quibus reperiuutur, anno editionis, 

 Etymologia et familiis ad quas pertinent, in variis classibus. Auctore L. 

 Agassiz. Solodur.' The plan of the work is evident from the title. 



In the department of Entomology, the Crustacea, including theEnfomostraca, 

 appeared in 1843, with the joint assistance of Prof. Burnieister, and the 

 Ins. Ilemiptera with that of Prof. Germar. On the completion of the 

 separate parts, a general summary of all the names in Zoology, with the date, 

 and a reference to the class and order will be given. Thus, on the one side 

 the important errors which arise from the multiplied use of one and the 

 same name will be prevented for the future, and, on the other, owing to the 

 mode of arrangement of the work, a summary view will be given of the 

 already established genera and other systematic divisions, so that the book 

 will, in a double way, be indispensable to every Zoologist, and will essentially 

 contribute to the diminution of the number of synonyms hereafter. 



Valuable researches on the Internal Structure of Insects 

 in the wider sense of the term, have been communicated by 

 Newport, in the Philosoph. Trans. Roy. Soc. of Lond. 1843, 

 p. 243. " On the Structure, Relations, and Development of 

 the Nervous and Circulatory Systems, and on the Existence 

 of a complete Circulation of the Blood in Vessels in the 

 Myriapoda and Macrourous Arachnida ; First Series ;" 

 which, although they immediately refer to a couple of defined 

 groups, are yet applicable to every class. 



This is true especially of the researches on the structure of the chain of 

 ganglia. The author had shown, nine years ago, that each of the nervous 

 cords between the ganglia was constituted of two columns, and in that 

 disposition had traced the distinction between the sensitive and motor nerves, 

 lie has now discovered that numerous filaments pass from one column to 

 the other ; he considers, however, that the inferior column alone goes to the 

 formation of the ganglia, whilst the superior lies upon them without any 

 perceptible enlargement The ganglion is sometimes formed by an enlarge- 

 ment of the nervous fibres themselves, sometimes by an interstitial deposit 

 of nucleated cells. There are besides, in the ganglia, bundles of transverse 

 fibres, and indeed as many as there are nerves given oil' on each side, so that 

 they form commissures between the corresponding nerves. They have no 



