TIELMINTHES. 
615 
18 in his monograph published in 1860. Altogether, Dr, Karl 
Moritz Diesing deseribes 132 species of Paramecocotylea, and 137 
species of Cyclocotylea, affording a total of 269 species referable 
to the order Cephalocotylea. Adopting our natural and more 
familiar nomenclature, the Cestodes or tapeworms may be said 
to number 250 known species, whilst the non-helminthic Penta- 
stomes (which, properly speaking, are members of the Acarine 
family) comprise 19 distinct forms. The following synoptical 
table explains Diesing's arrangement of the five genera of the 
Cyclocotylea : — 
CYCLOCOTYLEA. 
Tribe A. Cyclocotylea aprocta. 
Fam. 11. Tetracotylea. 
Tfenia, Sciadocephalus, Ephedrocepbalus, Amphoteromorphiis. 
Fam. 12. Octocotylea. 
Peltidocotyle. 
Tribe B. Cyclocotylea proctucha. 
Fam. 1,3. Hypocotylea. 
Here, again, one perceives the disadvantage of a uniformly 
artificial mode of classification, since Diesing, in order to make 
his subdivisions of the Cyclocotylea correspond with those of 
Parartiecocotylea, is obliged, as it were, to have recourse to the 
assumption of the possible existence of a third Cyclocotylean 
family (Hypocotylea). 
Apart from these unavoidable defects, it may be permitted us 
to remark, on the other hand, that the author's generic terms 
are often very happily chosen, whilst the specific characters are 
skilfully eondensed within the narrowest possible limits. The 
amount of research, as shown by the extended and accurate series 
of references, is simply astonishing. 
Bastian, H. C. On the Striieture and Nature of the Dracunculus, 
or Guineaworm. Trans. Linn. Soc. vol. xxiv. 1864. Read 
Feb. 19, 1863. (With two plates, pp. 101-134.) 
The author commences this valuable memoir with a tolerably 
full account of the various opinions entertained by the older 
writers respecting the natural history of the Dracunculus ; fol- 
lowing which, he gives an able criticism of the views enunciated 
by more recent authorities, amongst whom Busk and Carter 
are justly held to occupy the foremost place. The statements of 
Owen, Jacobson, Leblond, Wagner, and others are fairly con- 
sidered. The materials at the author's disposal are referred to as 
follows ; — ^‘1 have examined," he says, six speeimens of Filaria 
medmensis, all of which were taken from the lower extremities 
of a well-known surgeon of Bombay, by whom they were given 
to Dr. Harley," Professor of Medical Jurisprudence at Uni- 
versity College, London. 
The author's account of the manner in which these parasites 
