ene ay DR ODS OF. LTH BslIN DIAN MUSEUM. 
I.—THE DEEP-SEA COLLECTION. 
By James Rircute, M.A., B.Sc., Natural History Department, 
The Royal Scottish Museum. 
INTRODUCTORY. 
This paper contains a first instalment of the description 
of the extensive collection of Indo-Malayan Hydroids in the Indian 
Museum, Calcutta. To the Trustees of the Museum, represented 
by Dr. Nelson Annandale, Superintendent of the Museum, I desire 
to tender my thanks for his kindness in entrusting to me the 
identification of the collection. 
Notwithstanding the unadvisedness of adopting a bathymetri- 
cal line of demarcation in dealing with so mobile a group as the 
Hydroida, in which many species occur at exceedingly variable 
depths, this instalment confines itself to those forms which have 
been found in the deeper waters of the Indian seas, and for these 
reasons: Few littoral specimens were present in the collections 
received from the Indian Museum, and it is deemed better to leave 
over the description of such forms until additional shore and estua- 
rine collecting—undertaken by Dr. Annandale—shall have made this 
section of the collection more representative. On the other hand 
the deep-sea collection seems to be already fairly complete. 
Along with the deep water species I have recorded a few 
specimens, chiefly from the neighbourhood of the Andaman Islands, 
regarding which no indication as to the depth at which they were 
obtained was given. But it appeared more fitting, since they be- 
long to the same series of collections as the deep Andaman speci- 
mens, to consider them here rather than with the shallow water 
forms. 
GENERAL NOTES ON THE COLLECTION. 
Morphological.Under this head little of special interest has 
to be recorded. I must note, however, the occurrence, in the 
only species of A glaophenia found in the collection, of a peculiar and 
distinctive gonosome. Thisappears to be a modified type of cor- 
bula in which the protective leaflets, which are arranged in two 
tiers, bristle outwards from the body of the gonosome, while the 
sonangia are covered in and protected by delicate plates of chitin 
(see p. 16, pl. iv, fig. 7). 
