iç)i5-] Fauna of the Chilka Lake : Polyzoa. 125 



Victorella bengalensis, Annandale. 



1907. ? Victorella symbiotica, Rousselet, Proc, Zool. Soc. London I, p. 255, pi. xv, 



figs. 7-8. 



1908. Victorella bengalensis, Annandale, Rec. Ind. Mus. II, p. 12, fig. 1. 

 1911. Victorella continent alis , Braem, Trav. Soc. Nat. St. Pêtersb. XLH, p. 30, 



figs. 18-21. 



1911. Victorella bengalensis, Annandale, Faun. Brit. Ind.,Freshw. Sponges, etc., 

 pp. 191-198, fig. 37. 



1911. Victorella bengalensis , id., Rec. Ind. Mus. VI, p. 197, pi. xii, figs. 3, 7, 8. 



I cannot find any definite difference between this species and the form from 

 Issyk-kul in Central Asia described by Braem as Victorella continentalis . The latter, 

 however, seems to have been founded on young colonies just developing from resting 

 buds. The features in which V. bengalensis differs from Rousselet's V. symbiotica are 

 also of problematical value, perhaps depending rather on the direct influence of 

 environment than on anything inherent in the organism. In V .bengalensis, to use 

 the name provisionally, this influence is powerful in determining the method of 

 growth, and four distinct phases may be noted. First, there are young colonies de- 

 veloping from resting buds on objects the surface of which provides abundance of space. 

 In these the zooecia are short and almost entirely recumbent, closely resembling those 

 of Paludicella in shape. Older colonies vary in accordance with the nature of the 

 object to which they are attached. The phase most commonly found resembles a 

 thick fur in which the hairs are represented by upright zooecia, and grows on the 

 stems and roots of grasses and water-plants and occasionally on the shells of 

 Gastropod molluscs. When the colony, attached to supports of the kind, is being 

 overwhelmed by mud owing to the deposition of silt in tidal creeks, the stolons of the 

 secondary buds become greatly elongated and by their entanglement produce a 

 spongy mass; the individual zooecia in this phase of the species are almost entirely 

 vertical and often of considerable height. The simplest adult phase is that found 

 on the stems of the hydroid Bimeria fluminalis . In it the colony is much more 

 diffuse than in the two others, and the zooecia, though mainly upright, are more 

 definitely swollen at the base. This phase often approaches very close to the 

 European V. pavida, which is commonly found on the stems of Cordylophora lacustris, 

 a hydroid that resembles B. fluminalis in ecology and manner of growth. 



I was surprised not to find this Polyzoon in the Chilka Lake ; it is common in 

 the tidal area of the Gangetic delta and has been taken at Madras and also probably 

 at Bombay. In the Gangetic delta it usually affects brackish water, but has been 

 observed with Plumatella in a pond of fresh water near a tidal canal. At Madras 

 it was found on the carapace of a freshwater prawn. The food is perhaps restricted 

 to diatoms of a kind that were not observed in the lake, but on this point further 

 information is desirable. 



