Male Sexual Organs ? in the InfiL.oria. 49 



material, and then this colourless, oval, and transparent body 

 could be detected without difficulty. 



In prosecuting his researches into the nature of these hither- 

 to unknown parts, M. Ehrenberg began by examining if in 

 the groups of infusores which were most nearly allied to those 

 in which he found these bodies, he could find similar organs ; and 

 he commenced with the Rotatoria. The gradual contractions 

 and dilatations which are performed by the central organ of the 

 radiated vascular apparatus in the Paramecia, occurred to him as 

 an excellent peculiarity to assist him in his researches. He had 

 a long time previously discovered a vascular organ quite as con- 

 tractile in the posterior part of the bodies of a great many of 

 the Rotatoria; and this led him to compare it with the organ in 

 question, although it did not communicate with the radiating 

 canals having a central point. He had described and drawn 

 this organ in detail when lie dissected the Hydatina senta. It 

 is in intimate and very distinct connection with the testicles ; 

 and he concluded that its function is to subserve the function 

 or excite the activity of the internal genital members of these 

 hermaphrodite animals. It was on this account that he then 

 named it the ejaculatory muscle of the male seminal fluid. 



In the rotatory animals, the ovary appears to be reduced to 

 two cornea, and to produce only a few eggs at a time. In the 

 Polygastrica, on the contrary, the granular matter which is sup- 

 posed to be eggs, as they have been noticed to come from the 

 vent of the Kolpoda cucullulus in the normal state, is spread 

 throughout the whole body, and especially surrounds the intes- 

 tines and the vesicles. In judging from this great extent of 

 the ovaries, and from these differences in their organization, it 

 would appear very probable that there are also differences in the 

 form and distribution of the male seminal organs, and in the 

 contractile organ which accomplishes the hermaphrodite fecun- 

 dation. The mass of eggs being very large and very distinct in the 

 Polygastrica, it is very probable that the male genital organs are 

 equally so. Besides, such an organization Records perfectly 

 with the great and rapid fecundity of these animals. On the 

 other hand, the simplicity of the ejaculatory organs of the Ro- 

 tatoria agrees very well with the fact, that these infusores are 

 not capable of self-division ; whilst in the Polygastrica, which 



VOL. XX. NO. XXXIX. JANUAttT 1836 D 



