104 TEREBELLID.^. 



the additional item of the nephridia, however interesting these may be as corroborative 

 distinctions. 



In his second division, in which the branchiae are absent, all the nephridia are free, 

 though the anterior may vary in size from the posterior. Here are Leoena, Proclea, 

 Laphania, Lanassa, Phisidia and Spinosplisera. The first four and probably all form 

 a natural series. 



In the third group, which has branchiae, nothing is entered about nephridia, but the 

 hook-rows are single or absent and the branchiae are filamentary. In this division are 

 Thelepus, Streblosoma and Parathelepus. 



The fourth group is devoid of branchiae and the nephridial characters are not 

 entered. It contains Amoea, Poly cirrus, Lysilla and Hauchiella, the last (the Poly cirrus 

 tribullata of the author) having neither bristles nor hooks. 



The Terebellidae have various ectoparasites, generally Protozoan. Thus Gotlvurina 

 was met with by Schmarda on Terebella macrobranchia ; Bhabdostyla sertularium on the 

 branchiae and feet of the Amphitritea and on Leprsea lapidaria from Naples by 

 De St. Joseph; and Bhabdostyla arenicolce, Fabre-Domergue, has also occurred, and on 

 the tentacles of Nicolea venustula De St. Joseph records Ophryodend.ron anmdatorum. 

 Crustacean parasites are rare in the Amphitritea, but Sars mentions Terebellicola 

 reptans, a female of which was fixed to a Terebellid 1 and Levinsen Grypsidoums 

 Terebellse, which with its egg-sacs lived in the intestine of Amphitrite cirrata. 



Busch 2 (1851) describes and figures a pelagic Terebellid larva in its tube, similar 

 to that formerly recorded by Milne Edwards, and subsequently by Griard, B. Nordenskiold 

 and others. 



Several stages of Terebella Mechelii are given by Claparede and Mecznikow (1868). 

 They show the segmenting egg, the trochophore, the larva of two segments, and 

 lastly one of six bristled segments in the pelagic stage (so-called Wartelia) in its 

 transparent tube, with its complete alimentary canal, viz., proboscis, oesophagus, 

 stomach, intestine and vent, on each side of which is a papilla. A pair of segmental 

 organs occur opposite the first two bristle-tufts. They thus supplement the previous 

 stages described in Terebella conchilega by Claparede (1863). 



Willemoes-Suhm 3 (1871) found the larva of Nicolea in April in Kiel Bay, the 

 early forms being pear-shaped and ciliated; then they become more elongated, being 

 cylindrical and tapered at each end. The next stage has a conical snout and four 

 eyes, with three bristled segments and two papillae posteriorly. He describes the ova 

 of Terebellides stroemi as attached to sea-grass by a stalk, and gives an account of the 

 early stages (trochophores) with two reddish eyes and an otocyst. 



Hacker (1896) thought the Terebellids and Arenicolidae had not pelagic larvae, 

 for they only rotated in their galleries. Terebellides stroemi, however, has pelagic young 

 (Willemoes-Suhm). The same author 4 (1898) mentions a Terebellid larva from the 

 Sargasso Sea which had formed its tube of Radiolarian skeletons. As it was included 



1 'Christ. Vidensk.-selsk. Forhandl./ 1861, p. 46 (sep. copy). 



3 ' Bee-bach. Anat. u. Entwickel. Wirb. Seeth./ p. 73, Taf. xi, fig. 7. 



3 ' Zeitsch. f. w. Zool./ Bd. xxi, p. 388, Taf. xxxiii. 



4 < Plankton Exped. Polych., etc., Larvse/ p. 31, Taf. iv, fig. 39. 



