CHIROCEPHALUS. 
41 
considerable accuracy the peculiar apparatus attached to 
the head, which he considered part of the mouth. He 
carefully watched also the process of hatching the young 
from the egg, and was the first to characterise and figure 
some of the changes they undergo before reaching ma- 
turity. He calls it by the Linnean name, Cancer st agnails, 
and confounds it with the animal described by Schceffer. 
This confusion is kept up by Bose and Latreille, who take 
the details almost literally as given by Schceffer, but who 
quote the descriptions of King and Shaw, as synonyms for 
the same species as mentioned by him. Similar confusion 
pervades the writings of all authors upon this subject till 
the time when M. Benedict Prevost published an excel- 
lent paper upon the genus, in the ‘Journal de Physique’ 
for 1803, giving a very minute anatomical description of 
the animal, with a great many details concerning its habits 
and development, from the egg to maturity. This paper 
having attracted the attention of M. Jurine, of Geneva, 
then busily engaged in studying the Entomostraca of that 
neighbourhood, he wrote to M. Prevost, requesting him 
to send some of the ova of the little creature he had de- 
scribed so particularly. His request was immediately 
complied with, and M. Prevost sent from Montauban to 
Geneva a quantity of ova, wrapped up in moist paper. 
These, though they were four days on the road, M. Jurine 
with great care hatched, and succeeded in bringing them 
to maturity. Having submitted the animals so reared to 
frequent examinations and careful study, he was enabled 
to verify all M. Prevost’s facts and observations, while his 
accomplished daughter, Mademoiselle Jurine, faithfully 
portrayed them, as seen by the microscope. These 
drawings having been placed at the disposal of Prevost, 
and his original paper having received from his own hands 
some emendations and corrections, were all published, in 
1820, at the end of M. Jurine’s work on the ‘ Monocles 
qui se trouvent a Geneve and the information given is so 
full and precise, that little has been left to be added to the 
history of this curious animal. He does not attempt, 
