MICROSCOPICAL MEMORANDA. 175 



Williams, after seeing the membrane under this power, immediately ap- 

 proved of the process which rendered it so distinctly visible. 



Mr. J. S. Bowerbank then read a paper, being "Descriptions of 

 three species of Sponge, containing some new forms of organization," 

 a full abstract of which will be found at page 161 of this Journal. 

 This paper led to much discussion, in which the Author, the Chairman, 

 Mr. Dalrymple, Dr. Willshire, and others, took part. 



On the table was the Microscope which the Council ordered for 

 the Society from Mr. James Smith. This instrument possesses many 

 modifications and improvements, both in the construction of its frame- 

 work and appurtenances, and in its optical parts. We hope to be able 

 at some future opportunity to give them in detail. 



JKemorantta. 



David Don on a peculiar kind of Organs existing in the Pitcher of 

 Nepenthes distillatoria. These organs the late Professor Don named 

 " clathrophores ;" they occupy the lower half of the inside of the pitcher, 

 and have been described by Treviranus, Meyen, and Korthals. Doubts 

 still exist as to their precise function ; but it appeared to him probable 

 either that they are the mouths by which the fluid is poured out into the 

 pitcher, or that they are connected with the function of respiration. 



The cuticle of the upper surface of the expanded part of the petiole 

 of Nepenthes distillatoria is described as destitute of stomata ; that of 

 the under surface, as being furnished with numerous oval, or nearly 

 orbicular stomata, composed of two semicircular cellules with rectili- 

 near faces. That of the outer surface of the pitcher is also without 

 stomata, but covered, especially in the young state, with long subulate 

 hairs, frequently dichotomous, or furnished with a spur-like process at 

 their base. The outer surface of the operculum is sparingly furnished 

 with stomata, and clothed with hairs which are frequently branched 

 and fasciculate ; the inner has no stomata, but is furnished with clathro- 

 phores and clothed with hairs, which are often fasciculate, but mostly 

 simple. 



In Sarracenia purpurea the cuticle of the pitchers is described as 

 consisting of sinuously-lobed and somewhat stelliform cellules, with 

 numerous small, oval, closed stomata. The fibrous bundles are stated 

 to be composed entirely of long pleurenchyma, the parenchyma adja- 

 cent to which consists of beautiful spiral cellules. The hairs of the 

 inner surface of the operculum are simple, hollow, reflexed, subulate, 

 and marked with numerous longitudinal parallel lines or striae ; they 

 proceed from a somewhat elevated base. In the pitchers of Cephalotus 

 the stomata are large, oval, and closed ; the spiral vessels smaller than 

 in Nepenthes, and containing only a single fibre ; and the hairs which 

 form the fringed border are simple, obtuse, and transparent. Proc. 

 Linn. Soc. 1840. 



