Observations on British Zoophytes and Protozoa, 273 
zooid of the adult. It is therefore probable that the ova of 
these genera undergo a polymorphic " development of many 
months' duration, similar to that described by Carter as 
occurring in Amoeba verrucosa,* and that each ovum be- 
comes transformed into numerous Amoeboid zooids, which 
escape through the openings of the shell and form the pri- 
mordial segments of future Khizopods. 
With regard to the male element, I have only one obser- 
vation to record. Amongst a large number of dark-brown 
Gromias which I have possessed for many months, one 
appeared filled as to its upper part with a milky matter, 
which, when pressed out, proved to be a congeries of cells 
and large active molecules, such as are obtained from the 
sperm-sacs of Hydra viridis. I was not able to make out 
the tails of the spermatozoa ; but there could be no mistak- 
ing the characteristic shape and movements of the cells and 
molecules. The sarcode of the body in Khizopods is itself 
finely molecular in structure, and, when crushed, exhibits 
slight molecular movements ; but these movements are alto- 
gether different from those of the objects which I am per- 
suaded are the spermatozoa of Gromia. 
Since the foregoing paper was sent to the press, I have 
received the April Number of the " Annals," in which 
Schultze's discovery of living young in the chambers of 
Botalia is brought before the readers of this Journal. Pro- 
fessor Williamson, in his "Treatise on Kecent Foraminifera" 
(Kay Soc. Publ.) states, in regard to his Spirillina perfo- 
rata, He (Professor Ehrenberg) assigns to it the trivial 
name of vivipara, owing to the circumstance that just within 
the septal orifice of his specimen he found two small spiral 
shells, which had obviously found their way there by acci- 
dent ; from this unimportant circumstance, he concluded 
that the shell was viviparous." perforata is plentiful in 
the Firth of Forth, on Fucus serratus. Immediately after 
reading Schultze's paper, I examined a quantity of the sea- 
weed, and found two large specimens of S. perforata sur- 
rounded by a multitude of very small ones. In one of the 
large specimens three small living Spirillina^ existed. Eh- 
'f' Ann. Nat. Hist., eer. 2, vol. xx. p. 37. 
