ARCHER— ON A NEW SPECIES OF COSMARIUM AND PENITTM. 49 



The perforation of the tumour in the stomach of the Boa hy the 

 Ascarides is remarkable, because it is a mischief which the species of 

 Ascaris (A. lumbricoides) infesting the human intestines is not guilty of, 

 not being capable, from the conformation of the mouth, of boring or 

 penetrating the parietes of its abode, but using this organ wholly for 

 suction. 



Although the Ascarides of man, which sometimes exist to the num- 

 ber of three or four hundred in the intestines, may, from their migratory 

 habits, get into many inconvenient places — such as the pancreatic duct, 

 larynx, vermiform appendix, bronchi, biliary ducts, &c. — yet they have 

 not fair]y been blamed in those cases in which, death having resulted from 

 perforation of the digestive tube, these worms are found free in the 

 cavity of the abdomen; for in all such cases it is discoverable that either 

 ulceration or softening of the intestine had existed, or abscesses had 

 burst and opened a passage out of the intestine, along which the worm 

 made its way ; and it is by the existence of the track of a bullet or of a 

 shot that the presence of worms in the abdominal cavity of animals 

 killed by sportsmen is explicable. 



In this animal the peritoneal coat of the stomach was not interfered 

 with by the worms, nor were there any appearances of chronic or recent 

 inflammation of either the internal or external walls of the cavity. 



The meeting then adjourned. 



FRIDAY, APRIL 10, 1863. 

 William Andrews, M. R. I. A., President, in the Chair. 



The Minutes of the preceding General Meeting were read and con- 

 firmed. 



Mr. E. P. Williams recorded the occurrence in the county of Wex- 

 ford of the American Bittern, which had been shot in "December, 1862, 

 by Captain Doyne. 



The following paper was read : — 



Description of a new Species of CosMARrrai (Corda), and of 

 Penium (Bred.) By W. Archer. 



Family — Desmidi ace^: . 



Genus — Cosmarium (Corda). 



Gosmarium exiguum (sp. nov.). 



Specific Characters : — Frond very minute, smooth, oblong, rather 

 more than twice as long as broad ; segments sub-quadrate ; starch gra- 

 nule single, central. 



Locality : — Dublin mountains ; not very rare. 



General Description : — Frond very minute, smooth ; in front view, 

 rather more than twice as long as broad, constriction deep, linear, acute ; 



