G. GENERAL NATURAL HISTORY AND ZOOLOGY. 333 



twelve plates. The internal anatomy and metamorphosis are 

 quite fully given, particularly the different modes of disposi- 

 tion of the air-tubes and their stigmata ; also the varying 

 form of the digestive canal, which in one instance {Tetrany- 

 chus plumistoynci) sends branches even to the extremities of 

 the feet and the palpi. In Troschel's Archw there are sev- 

 eral papers of less importance on other families of mites by 

 Dr. Kramer. 



COLOEING MATTER OF THE MUREX SHELL. 



MM. de Negri state that, as the result of careful investiga- 

 tion into the coloring matter of certain moUusks, the Murex 

 trunciilus contains two coloring principles, one of which is per- 

 fectly equal to indigotine. This is obtained by exposing the 

 coloring principle of the mollusk to the air until it assumes 

 a violet tint ; then washing it with crystalline acetic acid, 

 which dissolves the tint. Water is then added to the acetic 

 solution, and the whole shaken up with chloroform, which 

 dissolves the purple. The chloroform solution leaves behind, 

 after evaporation, the residue, which is violet. Washed in 

 ether, this is deprived of the red principle contained in it, and 

 the remainder is redissolved in alcohol. It is well known 

 that the ancients preferred the secretion of the 3Turex braii- 

 daris to that of the 3L trunciilus. It is found that the secre- 

 tions of these two species are by no means the same, and that 

 their products from solution are different. In fact, the secre- 

 tion oi M. hrandaris is photogenic ; that is to say, it does not 

 become colored by the deprivation of light, while that ofi)/. 

 trmiculits becomes violet by contact w^ith the air. In refer- 

 ence to the studies of the coloring: matter found in the A. 

 ^'^>^(7^5, they remark that they have found chlorophyl in other 

 mollusks, identical with the coloring matter of vegetine. 3 

 B, December 23, 678. 



EIGHTH REPORT OF THE STATE ENTOMOLOGIS'f OP MISSOURI. 



The eighth annual report on the noxious, beneficial, and 

 other insects of Missouri, by Charles V. Riley, state entomol- 

 ogist, has just been received, and, like every thing from this 

 writer, contains much matter of interest to agriculture and 

 entomology. The noxious species to which special attention 

 has been directed in this report are the Colorado potato- 



