Resting Eggs, or Statoblasts of a Plumatella. 273 



that they were in good health, although persisting in their 

 inexplicable rest. The cold of winter was not likely to summon 

 their dormant powers to exertion, so they were allowed to re- 

 pose on a shady shelf, the glass jar being lightly covered over to 

 exclude the dust. By spring time the anacharis had died, and 

 the water was reduced to half its bulk by evaporation, leaving 

 many of the statoblasts high and dry on the glass. Fresh water 

 was poured in, and the vessel removed to a lighter place. 



On the 18th of May a few of the statoblasts were disco- 

 vered gaping, the shell having opened like that of a walnut. 

 A group were speedily transferred to a zoophyte cell, and 

 placed on the microscope stage; one polypide appeared just 

 out — just hatched, I would say, but we must remember that 

 we have to do with a peculiar kind of bud rather than with a 

 genuine egg; the tentacles of the new-born polypide were 

 beautifully expanded, but for an hour or two it was impossible 

 to discern the crescentic form, and it might easily have been 

 taken for a Fredericella, whose tentacles are arranged in a 

 beautiful bell-shaped pattern, like those of the common sea-side 

 members of this most interesting group. As far as I could 

 make out, the circular aspect arose from a close approximation 

 of the two arms of the crest-bearer, or lophophore, and the in- 

 conspicuous positiou taken by the tentacles on its inner side. 

 In another specimen the exit from the shell went on under our 

 eye, and the sketch which my wife made, and which forms a 

 tinted plate, gives a good idea of how the infant polyzoon 

 looked. 



The glass jar containing the main stock of statoblasts stood 

 in my study window, which has a north aspect, so, for the 

 sake of varying the circumstances, I placed a few dozen in a 

 bottle, and exposed them to as much sun as a dismal summer 

 afforded, on a southern greenhouse shelf, keeping off the ex- 

 treme glare by a thin paper screen. In this position three or 

 four developed themselves, but the greater warmth did nob 

 exert as much influence as might have been supposed. The 

 few specimens I obtained were used up in microscopic exami- 

 nations, and a pause ensued, which was not broken till the 

 22nd of August, when I noticed a few more young polypides in 

 the glass jar; those in the bottle remained as before. Since 

 that date I doubt whether any progress has taken place, and as I 

 did not succeed in keeping any specimen long enough to form 

 a series of new cells and branches, I cannot tell whether they 

 would have reproduced the compact entangled form or "gone 

 back/' as the florists say, to the simpler pattern in which the 

 P. repens is usually found. 



Probably in a good sized fresh -water aquarium in which the 

 natural conditions of a pond would have been more accurately 



