of the CO L , by the parts containing chloroplryll. He distinguishes 



period, when nitrogenous constituents predominate, is that during 

 which vegetation is most active ; the second, when the proportion 



respiration is comparatively feeble, the CO* evolved being again 

 almost entirely taken up by the chlorophyll, decomposed, and the 

 carbon fixed in the process of assimilation or digestion. He 

 found that the proportion of nitrogenous matter in leaves grad- 

 ually diminishes, while that of carbonaceous matter increases, 

 between autumn and spring. — A. W. B. 



Martenia probosc ides.— This is a very common plant in Ari- 

 zona and is very productive. Its large seed pods after being de- 

 prived of their epidermis are used by all the Indian tribes of Ar- 



is first to soften by means of water the black pods which are very 

 hard. They readily soften, and are then straightened, split into 

 the requisite strips and worked into willow baskets to form the 

 black ornamentations seen in those made by all the tribes of Ari- 

 zona.— Edward Palmer. 



ZOOLOGY. 



An Additional Character for the Definition of Rhyn- 

 invited the attention of my colleagues of the Academy to the re- 

 divisions of that order of insects. In the first of these I endeav- 

 ored to show that they formed a group which was equivalent to all 

 the others combined. The defining character of the group I 

 stated to be, that the posterior lateral elements (the prothoracic 



median line, in such a manner as to form a longitudinal suture be- 

 hind the end of the presternum ; in all other Coleoptera 2 the pro- 

 sternum ends in a vacant space, or extends so as to take part in 

 the articulation between the pro- and metathoracic segments. In 



