244 BULLETIN OF THE 



The larger part of the cavity of the male bell is taken up by an ovate, 

 sliylitly opaque mass, which is a sac inflated with spermatozoa. This 

 sac, like the sac which carries the ovum, fills almost the whole cavity of 

 the bell. The distal pole of the sac is closed. 



Free spermatozoa are obtained in great quantities by simply pressing 

 the body of the sac of the male gonophore, when they escape through 

 the ruptures in the walls. The spermatozoa are tlie ordinary tailed 

 variety with rounded, often pyriform heads, which are sometimes pro- 

 lonrjed into a pointed end opposite the tail. 



In the smaller female gonophores (PI. I. fig. 1), and also in some others 

 of lai-ger size, we recognize in the contained egg a transparent cell, ger- 

 minative vesicle, in which is a dot, and sometimes within the last are one 

 or more granules. The mass of the egg, however, is formed of a clear 

 substance, through which there extends a protoplasmic network, impart- 

 ing the appearance of a complex spongy mass of polygonal cells to the 

 egg contents. This network has not been figured or specially described 

 by others in the egg of Agalma, although it has been seen by Metschni- 

 koff and figured by him in Ejnbidia, Stephanomia, and Ilalistemma. 

 Although he neither figures nor specially describes this network in 

 Agalma, Metsclmikoff * may have referred to it when he says: "Die 

 vollkommern reifen membran- und kernlosen Eier [of Ar/ahui] zeigen 

 eine ahnliche Zusammensetzung wie die oben beschreibencn YAqv der 

 Epibulia aurantiaca und des Ilippojxjdms gleba, unterscheiden f sich 

 aber von ihnen durch ihre feincn rijthlichgelbe Farbung, welches sie 

 dcm Vorhandensein cines diffusen Pigmentes verdanken." I shall return 

 to these " cells " later, in my account of the progress of the growth of 

 the e^xg. 



Prccisel}^ how the spermatozoon comes in contact with the ovum, if 

 the latter is placed in a closed sac, is somewhat of a puzzle. The germ- 

 inative dot and vesicle disappear before this sac is ruptured. At about 

 this time one or two globules {pg.) were observed on the egg. In my 

 figure the nucleus and nucleolus have not disappeared. These changes 

 go on so fast, that T am not confident that both are fotmd together, and 

 the globules may have appeared after the disappearance of dot and ves- 

 icle. These globules seem to be the same as the " deformed spermato- 

 zoa " described in another genus by P. E. Miiller. If the disappearance 



* Loc. cit., p. 49. 



+ The stateinoiit of iletsclmikofT, p. 46 (quoted above), that the eggs of Hippopo- 

 flius rjlr.ha " mit einer freilich ausserst dlinnen Membran iiberzogen sind," would seem 

 to be another difierence. 



