Ndviculacea.'] iNFtrsoniAL animalcules. 477 



ramose stipes; bacilli generally in pairs, and smootli. 6. Rimaria, 

 connate in tables, at length, separating, except at their alternate 

 angles, where they cohere. 



SrNEDEA uhia {Vibrio hvpunetatm, M.) — Striated; truncated late- 

 rally ; as age advances the lateral ends become dilated ; upon the broad 

 side of the dilated end are seen three obtuse teeth, and two openings 

 between them. Often occurs in vast numbers, appearing as a white 

 incrustation, covering the stones on the banks of rivers in summer. 

 Dr. Lankester has noticed this in the Annan, Dumfriesshire; 

 wherever a mass of gravel was exposed to the air, the surface of 

 the stones appeared thus covered. With a pocket magnifier, they 

 resembled acicular crystals ; using a deeper power and examining the 

 wet stones on the edge of the water, they were mostly arranged in 

 a stellate form, resting upon filaments of Conferva. Size 1- 100th 

 long, 1 -2000th broad. Dr. L. says, the lorica of those from the 

 Annan is not striated, nor are their ends dilated. — fProo. Lin. Soc.J 

 Sometimes they are parasitic on Vorticella, or may themselves serve 

 as a basis for the attachment of other beings, as the Podosphenia 

 (f. 184) ; so that we have here an example of one parasite growing 

 upon another. Found both in fresh and brackish water. Size 

 l-280th to 1-lOOth. 



S. sigmoidea. — Striated ; large, slender, and sigmoid. Group 

 148 shews to the left a specimen undergoing longitudinal self-division ; 

 the figure on the right is a side view. The relation of the length 

 to the number of stripes is as follows : — Those individuals which 

 were l-720th long had ten stripes; l-570th, fourteen; l-480th, 

 fifteen; l-360th, twenty; l-280th, twenty-seven; l-140th, fifty- 

 four; l-120th, sixty; l-70th, one hundred and eight; l-48th, one 

 hundred and sixty; l-36th, two hundred and sixteen. 



S. capitula. — Very large, striated, linear, straight, of the form 

 shewn in group 185, which exhibits both a front and a side view; 

 granules yellowish green. Common, both living and fossil. Length 

 1-1 20th to l-40th. 



S. Gallionii. — Large, bacillar, smooth, linear and attenuate late- 

 rally; margin striated; stipes thick and curved. Length 1- 120th 

 to l-lOOth (P. 15, f. 34, 36). Marine. 



