QUATREFAGE’S HISTOIRE NATURELLE. 43 
hand willallow. The embryogeny of the Annelida is, indeed, 
a field of study which has been but little entered on, and 
which is most urgently in need of workers. M. de Quatre- 
fages himself has traced the development of Hermella, and 
gives a résumé of his work in this chapter. We may here call 
to mind Busch and Miiller’s arrangement of the different 
larval stages of Annelida into Telotrocha, Mesotrocha, Poly- 
trocha, and Atrocha, according to the varying development 
of the ciliated rings which characterise these larve. Clapa- 
réde has lately attempted a more complete classification, 
dividing the larve into two large primary groups—Mata- 
chete and Perennichete, the first of which is subdivided 
into the three groups Gasterotroche, Nototroche, Amphi- 
troche; the second into Cephalotroche, Polytroche, Atroche. 
M. de Quatrefages does not at all like this classification of 
Claparéde’s, since, a Polytrocha becoming an Atrocha in the 
course of development, and other similar changes occurring, 
his nomenclature will only give rise to confusion. He 
further observes very truly that we know very few facts 
relating to this subject, the larvee of scarcely thirty species 
haying been examined. He gives a list of these species, and 
references to the papers in which they are described. This 
list is really so valuable to any one who wishes to carry on 
investigations in this branch of inquiry, that we copy it here 
in full. 
ApuropitEA.— Polynoé cirrata—Sars, ‘ Wiegm. Archiv,’ 
1845, i, p. 11. 
Polynoé cirrata—Max Miiller, ‘ Miiller’s Archiv,’ 1851, 
p: 23. Désor, ‘ Boston Journ. Nat. Hist.,’ vol. vi, p. 12. 
Polynoé—Claparéde, ‘ Beobacht. iiber Anat. und Entwick. 
Wirbell. Th.,’ p. 80, pl. 8, figs. 7—11. 
EvnicEa.—Eunice sanguinea.—Koch, “ Eim Worte zur 
Entwick. von Eunice”’ (*‘ N. Deukschr. der Schweiz. Gesch.,’ 
vol, vii). 
LycormpEA.—Nereis diversicolor—Max Schultze, ‘ Ab- 
handl. der naturforsk. Gesellsch. zu Halle,’ vol. v, p. 213. 
Nereis.—Miine-Edwards, ‘Ann. des Sci. Nat.,’ 3rd ser., 
vol. iii. 
Puytiopocra. — Phyllodoce.—- Max Miiller, ‘ Miiller’s 
Archiv,’ 1855, p. 17. 
SyLLipEA.—Syllis pulligera—Krohn, ‘ Wiegm. Archiv,’ 
1852, p. 251. 
Autolytus prolifer—Kvrohn, ‘ Wiegm. Archiv,’ 1852, p. 66. 
‘ Miiller’s Archiv,’ 1855, p. 489. 
Autolytus cornutus.—A. Agassiz, ‘ Journ. of Boston Soc.,’ 
vol. vii, 1862, p. 392. 
