29 



Me., Aug. IG, 1857, in company with Pupa exigua, Say, and tlie 

 smaller Helices. 



Found generally on low lands, where they seemed to be sur- 

 rounded by water, though it has been found on higli lands where 

 the ground was comparatively dry. Mr. Charles B. Fuller, of 

 Portland, found them quite numerous in a grove of pines, — an 

 unusual place for Helices to be found in. 



Dr. C. T. Jackson observed that, having searched in vain for a 

 red dye in the red-bug {^Reduvius), he had found the whole insect 

 rapidly soluble, with effervescence, in nitric acid, forming a dark 

 brown solution. On dipping a piece of flannel prepared by an 

 alum mordant into this solution, and then into an ammoniated 

 solution, he obtained a deep rich orange and permanent dye ; it 

 does not take well on cotton fabrics. A permanent yellow dye, 

 and one which could be used as a basis for greens and browns, 

 would be a very desirable thing, as much of the yellow flannel is 

 dyed with chromate of lead, as well as with the yellow berry, and 

 might prove dangerous if worn next the skin. It does not make 

 a good pigment, as its lake is ochreous, and not a desirable color. 

 These insects are very abundant and destructive, and the possi- 

 bility of their being made available in the arts would add another 

 and a powerful motive for their collection and destruction. 



Dr. Jackson also made some remarks on the corrosive 

 properties of Mexican guano. 



This substance in twenty-four hours will destroy the bags which 

 contain it, in a few days will render a cask rotten, and in the 

 course of a short voyage will so dissolve out the oakum used in 

 caulking vessels as to render them leaky, as has been proved in 

 several instances, to the knowledge of Mr. P. A. Stone, of Bos- 

 ton. This guano has been so altered by the action of rain and 

 sea-water, that it presents an excess of phosphoric acid, in the 

 form of soluble acid phosphate of lime. Whether the solvent 

 action is due to free phosphoric acid, or to the presence of the 

 animal matter with it, is not satisfactorily determined. The am- 

 moniacal guano, such as that from the Chincha Islands, has no 

 such effect on cloth or wood. 



