Slee hee Ne Aw oy MB I OT TC Ag iene eG A. 
INTRODUCTORY NOTE. 
The following papers are the first in a series that I propose to 
publish as occasion offers. It will deal with Indian animals of 
different species found living together in a manner that apparently 
implies something more than fortuitous concurrence. Such rela- 
tions actually range in an almost unbroken chiin from parasitism 
on the one hand through commensalism to temporary, if not 
accidental association on the other. In these days of extreme 
specialization in systematic zoology, it is perhaps just as well 
that, even in describing new species, attention should be called 
not only to their taxonomic position but also to their bionomics. 
Many of the species described in this series will be Polyzoa or Cirri- 
pedia, but I do not pledge myself to restrict my investigations 
to any particular group or groups of animals and I hope to have 
the help of specialists from time to time. 
Nagat 
No. 1.—POLYZOA ATTACHED TO INDO-PACIFIC 
STOMATOPODS. 
By N. ANNANDALE, D.Sc., F.A.S.B., Superintendent of 
the Indian Museum. 
A biological feature of the Stomatopoda which they share to 
some extent, at any rate in Indian seas, with the Decapoda 
Natantia and Anomoura, is the rarity with which other living 
organisms are attached to any part of their body. In this res- 
pect they are in strong contrast with the crabs and Reptantia, 
which in a large proportion of cases have small Cirripedia (usually 
species of Dichelaspis or Poecilasma) attached to the gills, even 
when the external surface is quite clean. In the collection of 
Stomatopoda belonging to the Indian Museum, or at present on 
loan in Calcutta, Mr. Kemp and I have not succeeded in finding 
more than half a dozen instances of sessile organisms being 
attached to any part of the animal. 
In the case of a Sguilla, unfortunately not identified, from 
the Bay of Bengal a few immature barnacles of the genus 
Dichelaspis (probably D. warwickii) were found attached to the 
pleopods, while on the dorsal surface of the carapace and 
abdomen of an example of Sguilla holoschista from S. India 
there are several small Balani which I have not yet been able to 
identify. Mr. H. B. Preston is describing in this part of our 
