clii GENERAL SUMMARY OF SCIENTIFIC AND 



state in the tissue proper of the organ, the authors think the 

 phosphorescent tissue produces a substance which slowly ac- 

 cumulates in the cells independently of all nervous influence, 

 and of the same order with other secretions ; and that only 

 the act by which it is discharged is voluntary. The prin- 

 ciple rendering the cells luminous behaved like the noctilu- 

 cine extracted by Phipson. The abundance of urates in the 

 cells makes it probable that uric acid results from the photo- 

 spheric decomposition of the preceding coagulable compound. 

 The large number of trachese in the apparatus is doubtless 

 connected with the consumption of oxygen accompanying 

 the phenomena. 



The relation of insects to plants lias been fully discussed by 

 Hermann Mailer, Professor Gray, Dr. Hooker, Sir John Lub- 

 bock, Dr. Mellichamp, Mr. Riley, and others, in various jour- 

 nals and newspapers, showing the great popular interest 

 taken in the subject. 



The application of entomology to agriculture is in the 

 United States a matter of so much practical importance that 

 several of the states (New York, Missouri, and Illinois) have 

 salaried entomologists, whose reports are of great value. 

 Particularly that of Mr. Riley, which is replete with new 

 facts regarding the habits of injurious insects. It contains 

 a long and condensed article on the Phylloxera of the vine, 

 which will be of especial value to grape-raisers. Meanwhile 

 every pains is being taken in France to find out means of 

 preventing the attacks of this formidable pest, which has 

 hitherto baffled every attempt to reduce its numbers. Dr. 

 Lebaron's report on the insects of Illinois is taken up with an 

 account of the beetles, and will be the means of creating much 

 interest in the study of insects. The grasshopper of the 

 West has done incalculable damage in Minnesota and parts 

 of Kansas and Nebraska ; and it is to be hoped that our en- 

 tomologists will, from a study of its habits, be able to devise 

 some way of meeting its attacks with fair success. The 

 army worm of the South has been studied in Alabama by 

 Mr. Grote. He attempts to show that the insect hybernates 

 as a moth, and that it dies out in the central and northern 

 portions of the cotton belt every year, being replaced the 

 succeeding year by immigration from more southern local- 

 ities, and where the cotton plant is perennial. 



