36 'Slv. H. J. Carter on the Freshwater Infusoria of Bombay. 



At p. 234, under the head of " Development of the ovules/' 

 it is stated that the same process as that which takes place in 

 the development of the ovule of SpongUla " appears to take place 

 in the ovules of Evglena" and this, to a certain extent, may be 

 really the case ; but as the ultimate forms of the two organisms 

 are different, so there must be a point at which their develop- 

 mental appearances begin to differ. This, in the ovule of Eu- 

 glena viridis, consists in the evolution of a spiral structure, which, 

 when fully formed, appears to spring out in opposite directions, 

 and thus, with the diaphane, afford that means of vermicular 

 progression which Evglena always presents when void of, or with 

 only an injured or imperfect cilium (fig;. 17 a, b, c). 



I infer this from the following circumstances : first, that in a 

 watch-glass, where a number of the ovules of Euglena viridis 

 Jiad been placed for observation, about a hundred small Euglena 

 virides, closely corresponding in size with the largest ovules, 

 made their appearance, elongating and contracting themselves 

 incessantly for several days, without moving far from the place 

 in which they appeared to have been developed (on account of 

 the imperfect state of their cilium), and, being without chloro- 

 phyll, presenting exactly the same appearances as fully-developed 

 individuals in the same condition (fig. 18). Secondly, from 

 the ovules which remained on the sides of the basin from which 

 those in the watch-glass were taken, presenting, after a while, a 

 spiral line on both the flat sides of the compressed ovule, which 

 apparently, from its resiliency, caused these sides to become 

 prominent and obtusely conical ; thus indicating an advance of 

 development in these also as well as in most of those in the 

 watch-glass, which was arrested, probably, from want of proper 

 nourishment (fig. 17). 



Now when we consider that the cells of Euglena, which we 

 have called ovules, do not present any signs of an amyloid com- 

 ])Osition when treated with iodine, that the existence of the spiral 

 line proves them not to be mere oil-globules, while the cell of 

 Euglena ultimately developes a spiral structure in its substance, 

 as I have particularly pointed out in Crumenula texta, Duj.*, 

 and a number of minute Euglena virides made their appearance 

 among a group of ovules of this organism, carefully set apart in 

 a vessel for development; there can, I think, be very little doubt 

 that these cells, which are common in all the family, are in 

 reality their ovules. 



In the same page it is stated, that " instances however do 



occur where the ovules gain a cilium within the cell," &c. I 



doubt now if these are developments of the ovules, but rather 



products of the other development which I have shown to take 



* Annals, vol. xviii. pi. (J. fig. CO a, b, c. 



