OF HYDATIDS. 259 



amber colour ;* and some of the larger of these are 

 found to contain others. 



« A third kind of hydatid has been also describ- 

 ed, but which I have never yet seen, where a num- 

 ber of hydatids have been enclosed one within an- 

 other, like a nest of chip boxes. 



« The fourth kind may be called the cellular hy- 

 datid, as it is peculiar to the cellular substance of 

 the muscles ; the cyst of this kind is of considera- 

 ble thickness, and consists of several distinct lay- 

 ers, which sometimes acquire a cartilaginous hard- 



ness. 



« There is a fifth kind of hydatids, which, from 

 being compressed together, and forming a substance 

 about the size of a garden pea, has been mistaken 

 for indurated lymphatic glands. This kind has 

 not, so far as 1 know, been described. 



a The hydatids are firmly united to each other 

 by a very adhesive mucus, and by a thin membrane, 

 besides which each of them is enveloped by its own 

 proper capsule. These hydatids are very small, 

 being about the size of the ovula in the ovaria of 

 fishes. This kind is often found in the choroid plex- 

 us of the lateral ventricles of the brain, i-n cases of 



* See Case IV. The cyst of the hydatid contained four 

 pints of water, and a great many hydatids of different sizes; 

 some were about the size of a nutmeg ; others, as large as a bill- 

 iard ball, floated loose within the largest hydatid ; and within 

 several of the larger hydatids, there were clusters of small 

 sperical bodies, grouped together, which adhered to their inner 

 sides. 



