1904.] MARI-VB FAUNA OF ZANZIBAR. 323 



the length and smoothness of the tentacles, and eveiy detail of 

 the feet and seta;. The jaw-appai-atus shows chai-aeteristie 

 I'esemblances in its yellow colour, in the size and position of the 

 left azygos plate, and in the whole stiaicture and composition of 

 the lower jaws, of which Mai-enzellei-'s i-e^ji-esentation cannot be 

 surpassed as a, likeness of the same pai-ts in the pi-esent examples; 

 of Eunice indica. 



This extension of the i-ange of the species from the Red Sea to 

 the south of Japan is striking but not without precedent. 



Eunice siciliexsis Gr. (Plate XXII. figs. 8, 9.) 



Eunice valida, Graviei', op. cit. 



This highly specialised and almost cosmopolitan species is 

 found apparently wherevei' limestone suitable for its boi-ings 

 occurs, and so especially in the coral I'egions of the tropics, where 

 its abundance must be an important item in the list of causes 

 tending to the disintegration of living coral and coral-rock. In 

 East Africa it occurs whei-ever coral grows, and so is recorded 

 from every locality whei'e I collectetl, including the shore of 

 Mombasa Island (one small specimen), and from a depth of 10 

 fathoms in Wasin Harbour, with the notable exception of Cliuaka 

 Bay, where no coral occurs. Di-. E. P. Wright brought fi-agments 

 of a large specimen from the Seychelles in 1868. 



In the Maldives, as would be expected fi-om the abundance of 

 soft reef-limestone and gi-owing coi-al, the woi-m is very common, 

 being recoi'ded from the following stations : — 



Reef and sand-fiats of Hulule, Male Atoll ; seven specimens and 



fragments. 

 . Xorth Male Atoll, 25 and 35 fathoms ; three specimens. 



Minikoi Atoll, fi'om the lagoon sand, three ; and from the reef 



undei' boiilders, two. 

 South Nilandu, 25 fathoms, hard bottom ; one specimen. 

 Suvadiva, 28 fathoms, from dead coral ; one specimen. 

 From Mahlos Atoll, 20 fathoms, were collected fragments from 



among sand and i-ubble. 



On splitting a block of growing coral, or blocks formed by recent 

 growth, in very many cases two or thi'ee dull green cords stretch 

 across the fissure. Thei-e are portions of a specimen of this 

 species, the buri-ow of which is so long and tortuous as to be cut 

 across two or three times by any split though the block. The 

 burrow has a delicate parchment-like lining, at least in some cases. 

 The worm is also able to burrow in the soft sui-face of the reef- 

 edge on the east coasts of Zanzibar. 



It is remai'kable that none of the Maldivan specimens attain 

 to the lai'ge size of sevei'al of those from East Afi-ica, and the 

 majority of them are about half this size. The largest East 

 African examples measure 5 or 6 mm. in bi-eadth, and such a 



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