THE MEDUSOID EMBRYO. 299 



development within its tubular walls of as many 

 embryos. These, as they develop themselves in 

 succession, show evidence of life, in their contraction 

 and change of form ; the outmost one sometimes 

 occupying the mouth of the fleshy duct and filling its 

 diameter, at others retiring to some distance, leaving 

 the duct long and slender, between the extremity and 

 the embryo. 



I have not seen the escape of the embryo, but per- 

 ceiving that one and another had escaped, I searched 

 the water of the minute glass box in which the animal 

 was kept. There I found the little new-bom creatures 

 I was seeking, but in a shape that surprised me not a 

 little. A moment's recollection, however, of what I 

 had seen as the progeny of the allied Laomedea, 

 diminished my astonishment. (See Plate XIX.) 



The embryo, then, of Camp, voluhilisi^ a gelatinous 

 globose sac, about -^ inch in diameter, somewhat 

 orange-shaped, perfectly circular in vertical aspect 

 (figs. 1 and 2), but flattened at the top, and as it were 

 cut ofi'at the bottom (fig. 3). The whole surface is 

 smooth until we arrive at this truncate bottom, round 

 the edge of which runs a tubular cord or canal of wrink- 

 led gelatinous substance, through which, as I believe, 

 circulates a fluid. At least, I perceive minute clear 

 globules, one here and there, in diff'erent parts of the 

 canal, playing backward and forward with a dancing 

 movement, which indicates some fluid in motion there, 

 though I am not sure that it strictly circulates. The 

 truncate surface sometimes appears slightly funnel- 

 shaped, the sides inclining inwardly to a central 

 orifice, larger or smaller at the will of the animal, by 



