228 
0. BADHAM. 
prefers to place these larvae in the genus Bicidium, until 
they are proved to develop into the adult Pea cilia. He 
regards the occurrence of P. quinquecapitata in the 
same locality as Bicidium aequoreae as suggestive, and 
considers it not improbable that their differences are due to 
age. 
It is to be noted that there are so far described, according 
to McMurrich (2), seven species of Peach i a, and these, 
together with an eighth species described by Miss Wils- 
more (3), are as widely distributed as the medusophilous 
Actinian larvas. 
In conclusion, it would seem that the parasitism of these 
larvae is only compatible with the presence of a deep siphono- 
glyph having an external opening or conchula, and such a 
structure is possessed only by the genus Peachia, if we 
except the little-known genus Actinopsis, which is said to 
possess a double conchula. 
I wish to thank Prof. Haswell, in whose laboratory this 
work was done, for his kind help and advice. 
The figures were re-drawn by Mr. F. W. Atkins, of the 
Sydney Technical High School. 
Literature. 
1. Had don, A. C.— “Note on the Arrangement of the Mesenteries in 
the Parasitic Larva of Halcampa chry santhellum 
(Peach),” ‘ Proc. Hoy. Dublin Soc.,’ vol. v, 1886-7. 
2. McMurricli, J. Playfair. — “ On Two New Actinians from the Coast 
of British Columbia,” ‘ Proc. Zool. Soc. London,’ 1913, p. 963. 
3. Wilsmore, Leonora J. — “ On some Hexactinise from New South 
Wales,” ‘ Journ. Linnean Soc., Zoology," vol. xxxii, 1911. 
4. Quoy et Gaimard. — “ Zoologie du Yoyage de la corvette ‘Astro- 
labe,’ ” Paris, 1833. 
5. Pax, F. — “ Revision des types des Actinies decrites par Quoy et 
Gaimard,” ‘ Ann. Sci. Nat.,’ ser. 9, xvi, 1912. 
6. Haddon, A. C. and Dixon, G. Y. — “ The Structure and Habits of 
Peachia liastata (Gosse),” £ Sci. Proc. Roy. Dublin Soc.,’ new 
series, vol. iv, 1885. 
