HELMINTHES. 613 
Essay is partly reprinted from the Medical Times and Ga- 
zette/^ It contains, however, important additions. 
C. Papers published in Journals. 
Diesing, K. M. Revision der Cephalocotyleen. Abtheilung : 
Paramecocotyleen. Sitzgsber. Akad. Wiss. Wien, 1864. 
Vorgelegt in der Sitzung d. k. Akad. der AVissench. vom 
8 October 1863 (pp. 146). 
Diesing, K. M. Revision der Cephalocotyleen. Abtheilung : 
Cyclocotyleen. Sitzgsber. Akad. Wiss. AVien, 1864. Vor- 
gelegt in der Sitzung vom 5 November 1863 (pp. 74). 
The author of the well-known ^ Systema Helminthum ^ con- 
tinues, at intervals, his admirable series of Revisions,^^ which 
were so auspiciously commenced in 1855. As these memoirs 
can be had separately, it may be useful to indicate very briefly 
their several titles and dates in English : — Revision of the Cer- 
carise; 1855. Corrections and additions to the foregoing; 1858 
(pp. 54). Revision of the Myzelrainths ; section of Trematodes ; 
1858 (pp. 86, with two plates). Revision of the Myzelminths; 
section of the Leeches ; 1859 (pp. 43) . Supplement and emenda- 
tions to the foregoing; 1859 (pp. 33). Revision of the Rhyn- 
godca; 1859- Revision of the Nematodes; 1861 (pp. 141, with 
one plate) . Revision of the Turbellaria ; Rhabdocoelian section ; 
1862 (pp. 128 ). 
In the rather artificial and complex system of classification 
initiated by Dr. Diesing, the Cephalocotylea constitute his fourth 
order of Helminths, and, without altering his original plan, as 
regards the orders themselves, he has introduced into the 
Revisions a variety of minor alterations affecting the sections, 
suborders, tribes, and genera. For example, in the case before 
us, he divides the Cephalocotylea (or those worms supporting 
suckers) into two sections, namely, the Paramecocotylea or those 
wLich have oblong pits, depressions, or cup-shaped discs, and 
the Cyclocotylea or those possessing circular suckers. The 
misfortune of this method is, that in the case of the Parameco- 
cotylea it brings together, in one group, animals totally distinct 
from each other, such as Bothriocephali, Tetrarhynchi, and 
Pentastomata, whilst, on the other hand, the Teniae are iso- 
lated from their allies to form the division termed Cyelocotylea. 
Disregarding the ambiguity and confusion of ideas which this 
artificial plan necessarily entails (in the minds of all who are 
accustomed to a strictly natural method), these Revisions are 
otherwise, and in many respects, extremely valuable. The Para- 
mecocotylea embrace thirty-one genera, which are disposed by 
the author (and may therefore be tabulated) as follows : — ■ 
