638 Memoirs of the Indian Museum. [Voi,. V, 



Moreover, in the latter species the branchiae extend from the 7th foot to the 40th or 

 50th. 



There is no pharynx in this species. 



None of the specimens was sexually mature, and probably they are not fully 

 grown, so that changes may occur as growth proceeds. 



There is no doubt that this species has its closest affinities with P. antennata. 

 It resembles it, and differs from other species of Polydora, in the structure of the 5th 

 setigerous segment, which is only slightly modified, and in the appearance of the 

 crochets in the 8th setigerous segment and in their shape. In other ways the two 

 species are alike. I agree with Mesnil that these differences justify the separation of 

 P. antennata and the creation for it of the genus Carazzia, in which the present species 

 must also be placed. 



Habitat. — Five specimens were collected in October 1914, in a canal at Chingri- 

 ghatta, near Calcutta. The specific gravity of the water was 1-004. 



Family AMMOCHARIDAE. 

 Myriochele picta, sp. nov. 

 (Plate XXXI, figs. 30A-F.) 



Very numerous specimens of this species were included in the collection, all from 

 the Chilka Lake. Unfortunately, the tubes are so narrow and tough, and the animals 

 so fragile and firmly attached to the tubes, that it is almost impossible to extract an 

 entire specimen. Frequently, also, the posterior extremity seems to be missing, or 

 to have been regenerated to a certain extent. 



The tubes are very uniform in size, 7-1 1 mm. long, and only 2 mm. in width. 

 They are composed of a tough inner membrane, covered on the outside with small 

 quartz grains (fig. 30B). The posterior end of the tube is somewhat narrowed, and is 

 covered with rather smaller quartz grains than the anterior end. 



The worms themselves are 3-4 mm. long. No specimens containing sperm or 

 ova were observed, so that possibly the worms attain greater dimensions, but their 

 uniform size, whether found in February or September, tends to show that they are 

 fully grown. 



On the back of the head, opposite the anterior end of the mouth, is a conspi- 

 cuous patch of reticulate purplish brown pigment (fig. 30c). This patch is fairly 

 constant in occurrence, though of variable size and density. At the posterior end of 

 the buccal segment is a transverse dorsal band of similar pigment. A fainter band 

 may occur near the anterior dorsal margin of the first thoracic segment, and smaller 

 patches are sometimes found on other parts of the head, though these are frequently 

 absent, at least in the preserved animals. 



A specimen, apparently complete (fig. 30A), was extracted from its tube. It is 

 3-5 mm. long, and consists of the head and 16 setigerous segments, of which 3 are 

 thoracic and 13 abdominal. The head and buccal segments (fig. 30c) are quite fused, 

 and frequently marked off from the thorax by a constriction. The head is some- 



