336 



THE GUIDE TO NATURE. 



bone or fragment of glass may wound 

 or perforate the organ. It is believed 

 that many cases of appendicitis are, 



Small 



at first, catarrhal ; that is, the inflama- 

 tion is limited to the mucous lining 

 only. The organ being a lang, narrow, 

 blind sac, mechanical conditions rather 



favor the stagnation of anything that 

 may enter from the intestine. If the 

 substance contains pus forming bac- 

 teria, an infection may follow. It has 

 been noted that a condition of lowered 

 vitality induced by an acute indiges- 

 tion (at the head of the list), cold 

 congestion or an injury like a blow or 

 strain, often precedes the inflammation. 

 Influeza, rheumatism or any other 

 general infection may be a cause. The 

 whole reparative power of the appen- 

 dix is low, as might be expected in a 

 retrogressing organ, consequent y. mi- 

 crobic infection frequently occurs and 

 >light attacks of appendicitis may be 

 mi ire common than is generally 

 known. If the catarrhal inflammation is 

 severe, congestion and swelling of the 

 mucous membrane may be sufficient 

 to obstruct the cavity and cut off 

 drainage into the caecum. Then fur- 

 ther exudation of serum and mucus, 

 with bacterial growth, will produce 

 pus, distention and often a compres- 

 sion of the blood vessels leading to 

 gangrene, easy perforation and blood 

 poisoning. A previous attack of ap- 

 pendicitis, causing kinks or constric- 

 tions or adhesions to neighboring parts, 

 hampering the normal contractions 

 and the return flow, is always attended 

 by a lowered resistance to infection 

 and a predisposition to further attacks. 

 There is a steadily diminishing rate of 

 attacks after thirty years of age. 



YAID 

 THE LENS 



A Ti:i{Ri:STHIAL ALGA. 



avenue along a country road. The 



trees themselves were bearing a luxu- 



lt was toward the middle of a mild riant growth of Protococcus viridis, the 



November that I noticed splashes of minute, single-celled plants concealing 



what seemed to be a green stain, at the bark under a sheet of green, while 



the bases of the maples that form an on the damp ground those splashes of 



