EXTRACTS FROM FOREIGN PERIODICALS. S75 
who during his long career has been occupied with so much perseverance and 
success in entomological classification, has pointed out in the external structure 
of the other Pa^ri modifications hitherto unnoticed, and these he has made a 
basis for new divisions. In the edition of the Regne Animal published a few 
years before his death, he separated the Cenohites from Pagurus, on account of 
their long median antennae. Lastly, he established, under the name Prophylace^ 
another generic group, which he considers as equally belonging to the tribe of 
Pagurians, but concerning whose structure there is still much uncertainty.— An¬ 
nates des Sciences Naturelles. —[^We may perhaps be tempted to translate fur¬ 
ther from Dr. Edwards’s valuable paper in a future number.— Ed.] 
2. Some Observations on Helminthology, by Charles Leblond. —Not¬ 
withstanding the systematic works of the most celebrated authors, and the pa¬ 
tient investigations of the most distinguished anatomists. Helminthology is, per¬ 
haps, of all the numerous branches included in Natural History, that which pre¬ 
sents most gaps to be supplied, errors to be corrected, and uncertainties to be 
dispelled. 
What guides, indeed, does science possess with regard to the structure of many 
even of the commonest helminthological species ? What fables have not been 
received with indifference, and published, as they were collected, without criti¬ 
cism or investigation ? How many useless discussions have been carried on re¬ 
garding the systematic value of a circumstance, of an accident, remarkable in¬ 
deed, but accessory, and altogether worthless as a character ? Should the ento- 
zoaries form in the zoological series a class, a family, distinct, or well divided, 
without regard to their character of internal parasites, and after the mere con¬ 
sideration of their structure, among the different groups founded by all natur¬ 
alists on the organisation itself of the animals ? 
This then is the condition of Helminthology at the present day, but M. Le¬ 
blond feels convinced that it will not long remain in such a state. Here in fact, 
as elsewhere, synthesis has preceded analysis; but analysis, already once dis¬ 
carded, will necessarily return sooner or later to regulate the synthesis, and es¬ 
tablish it on a sure foundation. The ordinary advance of the human mind re¬ 
quires it. 
The blots which disfigure the history of the entozoaries, and which seem to 
lead us back to the early ages of Zoology, would not surprise us if they appeared 
in the older scientific works, at least if the animals occasionally present extra¬ 
ordinary and paradoxical forms ; but what can we think when they remain des¬ 
pite the recent discoveries in Comparative Anatomy, and when, effaced from time 
to time, they re-appear at short intervals, shining with all the pretensions of 
novelty ? 
Thus, sometimes limited to the zoological description of species, sometimes 
3 D 2 
