442 Mr. E. R. Blundstone. Glycogen in the [June 18, 



IX. " On the Occurrence of Glycogen as a Constituent of the 

 Vesicular Cells of the Connective Tissue of Molluscs." 

 By Edwin Richardson Blundstone, Scholar of Christ's 

 College, Cambridge. Communicated by E. Ray Lankester, 

 M.A., LL.D., F.R.S. Received June 2, 1885. 



The following results were obtained in connexion with a research 

 " On the Connective Tissue and Vascular System of Mollusca," on 

 which I acted as assistant to Professor Lankester, according to the 

 terms of a grant from the Government Grant Committee of the 

 Royal Society : other results will be published subsequently. 



The connective tissues of Molluscs, as presented by Helix, 

 Planorbis, Anodon, Cyclas, and Solen, may be divided into two 

 main groups. In one of these the constituent cells are little 

 advanced from their original mesoblastic condition ; they have an 

 irregular stellate form, and they are joined together by the tips of 

 their processes. In the other variety, which will be spoken of as 

 lamellar connective tissue, the cells are more irregular in form and 

 their processes more attenuated, but, by the deposition of an inter- 

 cellular ectoplasm in certain planes, the cells come to lie in plates or 

 films. These films form the walls of the sinuses and lacunae 

 (occasionally vein-like in appearance) of Molluscs. All the cells, 

 however, of the lamellar connective tissue do not lie embedded in 

 the films, for some of enormous size project into the blood, being only 

 attached by a small portion of their superficies to the film. 



These cells are the "vesicular cells" (Lankester) of the lamellar 

 connective tissue : they contain glycogen. 



1. Tissues operated upon. 



In extracting glycogen from Anodon I have made use of the mantle, 

 thus avoiding all contamination and complications of results on the 

 part of the liver, and, by rejecting the mantle edge, ventral to the 

 pallial muscles, have been able to work upon a region of the simple^ 

 composition, for with the exception of a very few muscular fibres 

 which pass from side to side of the mantle, the region operated upon 

 comprises only the two epidermes and the lamellar films with their 

 glycogenous cells. The blood offers no difficulties, as it readily drains 

 out of the mantle. 



2. Processes of 'Extractions, fyc. 



In extraction I have made use of the process and tests detailed for 

 investigating the liver of the rabbit for glycogen in Foster and 

 Langley's "Elementary Physiology," and also of those in the 

 admirable essay of Dr. Errera, to which I am much indebted. 



