Mr. Rainey on the Structure of the Cysticercus cellulosee. 145 



however, some considerations of a more theoretical kind, though 

 not of less importance. It will be asked, how the entozoon, in its 

 earliest condition, such as I have described it, finds access to the 

 interior of a primary fasciculus. Before attempting to answer this 

 question, I must observe that my description commences from a 

 condition of this entozoon so complete, that no one, on examining 

 it in this state with the microscope, will deny its perfect similarity 

 to those of the higher form. But there are other linlis in the chain 

 which I must now consider, and which so far have been omitted 

 only because I wished to keep that which is certain distinct from 

 that which is probable. Before the cells and molecules already 

 described accumulate in sufficient quantity to present the un- 

 doubted character above mentioned, they are found aggregated in 

 smaller groups, and even occurring individually in all the primary 

 fasciculi of the diseased muscle ; their quantity, and the size and 

 form of these groups, present the greatest possible irregularity in 

 the different fasciculi. In some the molecular deposit looks like an 

 early stage of fatty degeneration, but it has characters very different ; 

 one is the shape of the molecules, which resemble in all respects 

 those in the growing ends of an entozoon ; and another is, their 

 situation, which seems to be between the primary fibrillse, tending 

 to separate them longitudinally ; however that may be, it is an 

 abnormal condition, and always co-existent with the higher forms 

 of the Cysticercus ; and as the entozoon, as I have first described it, 

 could not possibly have taken on that form all at once, these groups 

 of molecules must therefore be looked upon as its antecedent 

 stage, or as portions of Cysticerci in progress of development. But 

 I also find in the specimens of muscle infested with these entozoa, 

 many of the capillaries and smaller blood-vessels filled with organic 

 molecules, which, so far as I am able to judge from the comparison 

 of such extremely minute bodies, seem to resemble those molecules 

 which are found in the primary fasciculi. The vessels filled with 

 these molecules have their coats so thin as to be inappreciable, and 

 some of the capillaries appear to be partially destroyed, and their 

 molecular contents diffused among the sarcous elements. As this 

 is an abnormal condition of the contents of these vessels, as well as 

 of their coats, and, so far as my experience goes, is not found ex- 

 cepting in conjunction with the earliest stages of the Cysticerci, I 

 am inclined to believe that the molecules in question are the same 

 as those in the primary fasciculi, and that it is by their coalescence 

 in these fasciculi that the formation- cells of the Cysticerci are 

 formed. 



Addendum, Dec. 6. — After an entozoon has left the interior of a 

 primary fasciculus, and arrived at the space between the muscular 

 fibres, it loses its ciliated investment, and increases in breadth. Its 

 margin now seems to be formed entirely by the convexities of 

 the globular masses of cells of which its body appears to be made 

 up, causing it to present a crenate form similar to that of the ven- 

 tral portion of the perfect animalcule, with this difference only, 

 that these cells are compressed. The next change which is visible 



Phil, Mag, S. 4. Vol. 12. No. 77, Aug, 1856. L 



