THE CROWN ANIMALCULE. 37 
is situated on the dorsal aspect, at the point where the swelling- 
trunk abruptly narrows to the origin of the foot (plate iii. e). 
Thus we have followed the alimentary function from its 
commencement to its termination, and have found that an 
organisation, not a little elaborate and complex, is provided for 
this object. 
The Stephcmoceros is a voracious feeder. Elirenberg saw large 
Naviculce devoured by it, and in one individual a Gonium pecto- 
ral c. He also saw that large infusory, Stent or, captured by it. 
Ley dig witnessed the seizing of a great TracMlmm, of various 
other Infusoria, and of the smaller Rot if era. I have myself 
seen the animal capture and devour scores of the Infusoria 
already named, in quick succession ; and on one occasion ob- 
served one feeding on the young of Floscularia cligitata, which 
were being hatched in considerable numbers in the same water. 
The Reproductive Organs. — The reproductive organs occupy 
a very considerable portion of the bulk of the animal, and are 
sufficiently conspicuous at all times in the adult. Judging from 
analogy, I presume the Stephanoceros to be dioecious; that is, 
that the males and females are distinct individuals ; but I have 
not had any opportunity of detecting- the male, nor, so far as I 
am aware, has any other observer. It will probably prove to 
be very unlike the female, and to have much the same form as 
the rudimentary young-, before the development of the arms ; to 
be destitute of masticatory and digestive organs, and to have 
a conspicuous mass of opaque white matter within the interior. 
These characters mark the male sex in the Rotifeka generally.* 
A bent or rolled ovary (plate iii./) occupies the greater part of 
the ventral region of the female, within which eggs may generally 
be seen in various stages of development. I have seen as many 
as seven eggs developing at one time in one individual. The 
undeveloped portion consists of a clear sac, containing a viscid 
granular jelly, often slightly turbid, in which are placed trans- 
* Dr. Leydig mentions having found among Stephanoccri that he was 
keeping for observation, a young animal possessing somewhat of the vermi- 
form figure, with a proboscis-like head, furnished with four projecting arms. 
The pair of eyes were discernible. Two considerable tubular appendages 
projected from the trunk-like process of the head, which were ciliated at 
their extremities ; the cilia which at birth are set round the tip of the foot 
had disappeared, but were very evident in the abdomen, near the sac con- 
taining the atoms, which he considers urinary. The. jaws had the ordinary 
structure. He mentions having also occasionally found another variety, which, 
together with the figure of the adult, had five arms, but was without any 
apparent sexual organs, while the foot and body were entirely occupied with 
fat globules. If either of these abnormal forms was the male, I conjecture it 
was the latter ; for the presence of the well-formed jaws in the former seems 
to exclude that form from the masculine sex. Still it was a very curious 
variation. 
