32 



ternal capsule is another one closely united to it, and 

 containing the scolices ; both of them again being con- 

 tained in a tough, fibrous covering, variously colored, 

 according to the organ in which it is placed, closely 

 adherent to the surrounding tissue, abundantly sup- 

 plied with blood-vessels, and sending out into the 

 organ where it is found prolongations of connective 

 tissue. 



. The external covering is of an albuminoid consist- 

 ence, laminated, containing no fibres, fibrils, or cell- 

 ules (Davaigne). The internal vesicle (the germinal 

 membrane of Goodsir) is a fibrillated, granular struc- 

 ture, containing a vascular system and calcareous cor- 

 puscles (Kiichenmeister). In its interior is found an 

 almost colorless, transparent, limpid fluid (Moquin- 

 Tandon). It is upon* the interior of this membrane 

 that the Echinococci are formed. 



This takes place in the following manner : 

 From the internal vascular layer of the Echino coccus 

 vesicle spring small buds, which form conical or vil- 

 lous-like elevations, sometimes measuring 0*4 mil. 

 These become transformed into small brood capsules 

 0-07 to 2 mil. in diameter, and in these the scolices 

 or buds are formed. This process, which at first 

 adheres by a tolerably broad base, becomes in this 

 way cleared, its contents more fluid ; and a small 

 globular vesicle, adhering to the inner wall of the 

 Echinococcus, is found, presenting an external struc- 

 tureless epidermis and an inner granular layer. In 

 the granular layer of these processes, which have been 

 dilated into vesicles, we observe vessels, which are con- 



