106 PROCEEDINGS OF SOCIETIES. 



presence of these Bacterian forms might be regarded as character- 

 istic ill certain species ; so much so that a Cosmarium had been 

 described by Mr. Lobb as " spinous," and possessing "rays," and 

 named Cosmarium radiatum (' Quart. Journ. Micr. Sci.,' vol. xiv, 

 p. 56), but Mr. Archer ventured to suspect erroneously so, and 

 fancied the so-called "rays" might in reality be simply these 

 strisa in the mucus. Sometimes these bacteria near the perij^hery 

 become dislodged and "wriggle off" w ith themselves, but their 

 movement is " lazy," comparatively speaking ; sometimes a little 

 pressure facilitates their removal and their becoming free. Similar 

 bacteria also sometimes occur in the periphery of Volvox glohator, 

 but there they lie in a tangental position. Chlorophyllaceous 

 algae are seemingly more prone by a good deal than Phycochro- 

 maceous forms to thus harbour bacteria (themselves doubtless to 

 be regarded as Phycochromaceous algae), but the former, as a 

 rule, have more mucous envelopes, and thus form a better nidus. 

 It must not for a moment be supposed the algae are in any 

 decaying or abnormal condition ; on the contrary, the presence 

 of the " bacteria " is most marked in the most healthy and 

 vigorous examples, and in various forms (Desmidieae and others) 

 they are pretty constantly and more or less characteristically 

 present. As to lioio these " parasitic " bacteria become deve- 

 loped in the position adverted to, Mr. Archer could not hazard 

 a conjecture, but their comparatively regular radiant, though 

 interrupted, linear disposition (around some globular forms, 

 almost calling to mind under a moderate power some " Actino- 

 phryan") and their habitual presence seemed sufficiently re- 

 markable ; at any rate such a peculiar nidus for these indeed, 

 in some form or other, omnipresent existences, Mr. Archer 

 believed had hardly been noticed. 



August l^tli, 1875. 



New Species of Synedra. — Eev. Eugene O'Meara brought for- 

 ward a new species of Synedra, lately found by him in a swampy 

 place on banks of Eoyal Canal, near Kilcock, Co. Kildare, and 

 which he named Synedra spathulata : — Frustules very large, 

 length 00130", in front view wider at the ends than at the 

 middle; greatest breadth 00012", ends straight; in side view 

 wider at the middle and gradually attenuated towards the ends, 

 at some distance from which (0-0025"), bending inwards and then 

 outwards, then suddenly constricted towards the broadly capitate 

 rounded extremities. 



Young of Water Snail exhibited. — Mr. Crowe showed specimens 

 moving by their cilia still in ovo, a pretty example of " pond life." 



Peculiar globular problematic enlargements ofMgcelium ofPeni- 

 cillium glaucum hitherto unobserved. — Dr. McNab showed ex- 

 amples of the Common Blue Mould, Penicillium glaucum, which 

 he had cultivated for fifteen days on moist bread. The mycelium 

 had produced an abundance of conidia-spores, but in addition 

 peculiar swellings of the mycelium had been observed. These 



