240 TEREBELLIDiE. 



each. The third species (specimen) had forty tentacula, but these 

 organs totally intercepted the view of the branchiae. 



*'This species constructs a semicylindrical sheath of sandy or 

 muddy particles, which is always of insufficient dimensions to cover 

 the body, or to receive the head. None of any other form has been 

 seen. This sheath is frequently abandoned and as often resumed ; 

 neither does the animal restrict itself to the construction of one 

 sheath only. 



" A peculiar feature in its history is its producing 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 is very thin, rather irregular, and composed of the finest 

 threads, almost invisible from their slenderness and extreme trans- 

 parence. Neither the mode of formation or extension, nor the 

 expedients for securing their extremities are obvious. Such a web, 

 from the specimen 9 lines long, covered an area 15 lines square. 

 This is plainly a work of some exertion, as the threads, sometimes 

 amounting to fifty, are fixed to the side of the vessel as high above 

 the bottom as equals the length of the weaver, or more, and they 

 also extend below, there to be secured. Thus it is evidently an 

 artificial work, and it receives successive accessions. The specimen 

 continued its work about three weeks in May, but although surviving 

 a month longer, it wove no more." — DalyelL 



*** Branchiae one pair only. 



10. T. maciilata, body mottled with variegated colours, wherein 

 brown, green and yellow predominate. Length 1|^" ; breadth 1'". 



Terebella maculata — the Spotted Terebella, Dalyell, Pow. Creat. ii. 

 203. pi. 28. f. 10-19. 



Hab, The coralline region. 



Desc. Body slender, with twenty to twenty-two tentacula about an 

 inch long. Branchiae arbuscular, in one pair ; " behind them stand 

 a pair of short, obtuse, pellucid stumps, which are not distinguished 

 by obvious peculiarities." Tentacula spotted with brown, and " a 

 row of short obtuse teeth, somewhat apart, border each side of each 

 tentaculum, such as have not been remarked in any of the others." 



*' This is the most beautiful of the genus, mottled, patched, or 

 speckled with variegated colours, wherein brown, green and yellow 

 predominate. A longitudinal light line traverses the speckled olive 

 back ; the root of the pencils is bounded by a dark line, and a stripe 

 within two darker lines runs down the belly. Faint green stains the 

 tentacula, their row of oblong or oval spots down the middle con- 

 tracting or dilating along with their action. 



" The spotted Terebella constructs a very compact, small, cylin- 

 drical tube of minute grains of sand, which is prolonged by irregular 

 curvatures. In the natural state it is attached to coraUines or similar 

 marine products, with their slender filaments alternately interwoven 



