414 
THE VOYAGE OF H.M.S. CHALLENGER. 
Family Hekmellid^e. 
The number of S23ecies j)rocured by the Challenger is comjjaratively small, probably 
because the grouj) is a shallow water or littoral one, as, indeed, the localities given 
by the foreign authors together with the habits of European forms shoAv. 
Kinberg describes seven sj^ecies, of which six are new, and under no less than five new 
genera. Schmarda gives four sjDecies, chiefly from the littoral zone. Grube describes 
one from the PhilijAjDines and one in the series collected by the “ Gazelle.” 
The occurrence of Nematoid j^arasites and Gregarinae in the alimentary canal is 
interesting. 
It is curious that no larg^e masses of the tulles of the Herniellidse come either from 
the Cape or the Australian region where they are common. 
Dr. Baird ^ states that an examjde of this grouj) (Sabellaria saxicava) bores in 
somewhat soft rock in Esquimalt Harbour, VancouA^er Island. This is an unusual 
feature. 
Sabellaria, Lamarck. 
Sabellaria [Pallasia) johnstonii^ n. sp. (PL XLVII. figs. 5, 6 ; PI. XXVa. figs. 16-23). 
Habitat . — From the littoral region, St. Vincent, Cape Verde Islands. 
A species of considerable size, measuring about 40 mm., inclusive of the tail, and 4’5 
in diameter at its widest portion. 
The body is divided into three Avell-marked regions, viz., the cephalic, anterior, and 
posterior, and in addition the tail constitutes a long a 2 )peudage. 
The cephalic region is sj)lit from the anterior margin to the base of the dorsal hooks 
superiorly, and ventrally as far back as the mouth. This Avide division gives the anterior 
region a characteristic aj)pearance, which is further intensified by the dark brownish 
mottling of the dorsal aspect. Moreover, a dark broAvn belt runs along the outer margin 
of the 023ercular region, and as the j^apillse in this are pale, they aj3pear like a series of 
white studs. From the dorsum the dh^ergence of the halves of the opercular region is 
very marked, the junction being characterised by a broad groove Avith a chitinous hook 
at each side. These hooks (PI. XLVII. fig. 5) are large and poAverful, and strongly 
curved toward the someAvhat sharp extremity. A reserve hook of similar shape is present 
at the base dorsally, its unAvorn tip being more acute than the older. These organs are 
probably of considerable importance in the economy of the animal, as for attaching it 
to the margin of its tube or other convenient structure. Unfortunately, however, no 
1 Proc. Zool. Soc. Lond., February 10, 1863. 
'■* After Dr. George Johnstoa, of Berwick-on-Tweed, whose labours amongst the British Annelids deserve gratel'ul 
remembrance. 
