304 THE AQUARIAN NATURALIST. 



more sluggish, and the gluten appears to be secreted 

 in smaller quantities, their progress is slower in pro- 

 portion. 



The extremity of the tube, which appears at the 

 surface of the sand, is generally ornamented with a 

 number of branches composed of single rows of sandy 

 or shelly particles. These are formed accidentally 

 from time to time by the adhesion of sand to the 

 tentacula when thrown out in quest of prey. The 

 gluten exuding from the tentacula cements the grains 

 of sand together, as may be plainly seen in animals 

 kept in confinement. 



TEREBELLA TEXTRIX. " The Weaver" 



The species thus named by Sir J. Dalyell is of very 

 small size, varying from about an inch to an inch and 

 a half in length. It constructs a semicvlindrical sheath 



O V 



of sandy or muddy particles, the dimensions of which 

 are always insufficient to cover the body or to receive 

 the head; and this sheath is frequently abandoned, 

 and as often resumed ; neither does the animal re- 

 strict itself to the construction of one sheath only. 



The most peculiar feature, however, in its history 

 is, that it manufactures a real cobweb, as distinct as 

 that of the spider, with which it covers itself, and 

 which also frequently, if not always, serves to support 

 its spawn. The texture of this remarkable web is 

 very thin, rather irregular, and composed of threads 

 so fine that they are almost invisible, from their 

 slenderness and extreme transparency. Neither the 

 mode of formation or extension, nor the expedients 



