528 Miscellaneous, 



the juices drawn from the soil become less abundant or cease alto- 

 gether. 



The experiments which I described in a memoir read to the 

 Academy on the 2.)th of July 1853, prove in the most evident 

 manner the course of the descending sap ; for when obstacles are 

 opposed to the progress of this sap, by means of ligatures, or of 

 spiral, annular, or semicircular decortications, the course of the sap 

 may be changed at pleasure. It then gives origin to very sinuous 

 vessels, presenting vertical parts and others oblique or horizontal, 

 which are always formed of cells elongated vertically, that is to say, 

 parallel to the axis of the stem, and of which the form, which is not 

 generally changed, is similar to that of the surrounding cells. The 

 sinuosities of these vessels show the current's of the sap progressing 

 through the cells of the generative layer, turning in all directions to 

 find an issue, perforating the cells from above downwards or hori- 

 zontally, according as the current is vertical, oblique or horizontal. 



All these facts prove evidently that it is the circulation that pro- 

 duces the vessels, — that is to say, that it is the function that creates 

 the organ. 



Since the circulation exists before the vessels, when there are 

 only simple cells through the walls of which the sap filters, the ob- 

 jection made by some anatomists to the existence of the circulation 

 in the laticiferous vessels, an objection founded on the cellular 

 structure of these vessels in certain plants, does not possess the 

 importance which they assign to it, as we see the dotted and striped 

 vessels, &c., formed by a current of sap pre-existing through im- 

 perforate cells ; and moreover these anatomists should consider that 

 there is not a living cell which is not traversed by juices, although 

 the great majority of these cells do not present any perforation 

 visible by means of our most powerful microscopes. And then 

 there are laticiferous vessels which are evidently composed of super- 

 posed cells, the transverse partitions of which present very wide 

 apertures (the laticiferous vessels of Musa, formed of large cells 

 with very thin walls, are fine examples of this). — Comptes Bendus, 

 Oct. 5, 1857, p. 466. 



Sepia officinalis. 



To the Editors of the Annals of Natural History. 



Weymouth, December 14, 1857. 

 Gentlemen, — The beach at Weymouth was this morning strewed 

 with the Cuttle-bone {Sepia officinalis). Within the space of half a 

 mile I believe I might have gathered a thousand. In no instance 

 could I find a portion of the animal. Apparently there has been no 

 weather to account for such an unusual occurrence, it having been 

 moderate for many days, with a slight southerly wind. 



This mollusk is but rarely found here, though after a storm a few 

 stray specimens of the so-called bones are thrown up. 



I am. Gentlemen, your most obedient Servant, 



Robert Damon. 



