66 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
are to bo found in South America, Australia, New Zealand, the Philip- 
pines, Madagascar, and North-Eastern India. After dealing in separate 
chapters with the various organs and systems, the author proceeds to 
discuss the affinities of the family. 
If we regard them as ectoparasitic Trematodes, then their integument 
is quite exceptional, for they have a complete distinct epithelial layer ; 
in this respect, indeed, they approach the Rhabdocoele Turbellaria, and 
the presence of vibratile cilia in T. minor and T. Bendy i makes the 
resemblance very close. Other points of similarity are the presence of 
rhabdites in the integument and the characters of the intestine and its 
epithelium. The excretory system is quite peculiar, but more nearly 
resembles that of ectoparasitic Trematodes than that of Rhabdocoeles. 
The comparatively large brain, the rich development of nerves 
running forwards, the three pairs of posterior trunks, and the highly 
developed subcutaneous nerve-plexus give Temnocephala a high place 
among Platyhelminths ; but, as has been shown by Lang, all these points 
are to be seen in Tristomum molse. In the structure of the reproductive 
organs the resemblances to Rhabdocoeles are more marked than those to 
ectoparasitic Trematodes ; perhaps the resemblance is closest in the 
Yorticidae. A remarkable point of resemblance is in the system of 
accessory glands secreting rounded granules connected with the male 
apparatus ; von Graff’s account of these structures as seen in Rhabdocoeles 
applies equally well, word for word, to Temnocephala. In having a 
direct development it agrees equally well with the monogenetic Trema- 
todes and the Rhabdocoela. 
On the whole, Prof. Haswell is inclined to think that the Trematode 
affinities of this parasite somewhat predominate over the Turbellarian. 
The large ventral sucker, the excretory sacs, and the nervous system 
may be set down as decidedly Trematode and not Turbellarian in 
character. The preponderance, however, is only slight, and little fault 
can be found with a systematist who should regard the Temnocephaleae 
as aberrant Rhabdocoeles specially modified in accordance with a peculiar 
mode of life. 
Apparently New Type of Platyhelminth.* — Prof. W. A. Haswell 
has found in the burrowing crayfish of Gippsland, Victoria ( Eugseus 
fossor ), a remarkable new parasite which may be a Trematode. He 
proposes to call it Actinodactylella Blanchardi. The whole animal, 
which is very soft, measures about 1 mm. by 0*3 mm., and is pear- 
shaped in form. There is a pair of tentacles on the cephalic lobe, and 
behind these there radiate out from the lateral margins of the body five 
more pairs of tentacles of relatively considerable length when fully 
extended. The animal moves exactly after the manner of a leech. At 
first sight Prof. Haswell was inclined to regard his find as allied to 
Temnocephala. 
Although, however, it is Trematode-like in general form, in the 
possession of anterior and posterior suckers, in the absence of vibratile 
cilia, and in the general characters of the alimentary canal and repro- 
ductive apparatus, it differs in very important points. Not only has it 
marginal tentacles and a nucleated epidermis, but it has a remarkable 
* Macleay Memorial Volume, 4to, Sydney, 1893, pp. 153-8 (1 pi.). 
