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a large number of segmenting ova, and not a few ciliated embryos. 
In two days the number of these latter had increased considerably 
and they could be seen with the naked eye moving about freely in 
the upper layers of the water. ‘They all died off about the 4th day. 
Preparations of the remainder of the gland showed that in it the 
ovarian and testicular tissue were not separated from each other by 
any sharp line of demarcation, but that they merged gradually together 
in such a way that islands and outlying processes of the one could 
be found in tissue belonging mainly to the other. While all stages 
in the development of the ova could be seen, the spermatic tissue was 
too ripe to show details of spermatogenesis. It was noted that in 
those parts of the gland which were purely ovarian none of the ova 
had gone on to segmentation. Evidently fertilization had taken place 
only where ova and spermatozoa were in close contact. 
Some kidney tissue having been cut away along with the genital 
gland, the sections at one part showed a communication by rupture 
between these two tissues, by way of which the sexual products were 
beginning their outward journey. Here, spermatozoa, and ova both 
segmented and unsegmented were found among the kidney tissue. 
This case of hermaphroditism is interesting, in the first place as 
being an exception for Patella and its class, and in the second place 
as showing a kind of hermaphroditism much simpler than is usually 
found in the monoecious gastropods while it approaches the type seen 
in such lamellibranchs as the common oyster. 
The peculiar habits and structure of the limpet might seem to 
give some rationale for this occasional variation. For as the limpet 
is solitary and practically fixed, as it possesses no organs of copulation 
and no sexual congress of any kind has been observed; the meeting 
of ovum and spermatozoon would seem to depend on chance, and on 
that account an occasional hermaphrodite might be of benefit to the 
species. But the number of such variations is too small to allow this 
consideration much weight. Apparently they have hitherto escaped 
observation and out of about 250 specimens examined I found only 
three hermaphrodites. One of these showed an excess of ovarian over 
testicular tissue, the distribution of both being patchy all over the 
gland. In the second the amounts were more equal, one side of the 
gland being purely male and the other female. In the third there was 
only a small patch of ovarian tissue, the main part of the gland being 
purely testicular. 
Considering the habits of the limpet it is obvious that those limpets 
which are placed on a high tidal level will have a much shorter time 
in which to feed, and will find food less abundant and rich than those 
Anat, Anz. XII. Aufsätze, 28 
