376 Prof. M'Intosh's Notes from the 



head is somewhat similar to that of Ophelia liinacina, tlic 

 snout being acutely conical, and the mouth formin<^ a trans- 

 verse slit behind it, as in that species. The enlarged anterior 

 region of the body is longer in proportion to the rest, and 

 there are only about twenty-three bristled segments, instead 

 of thirty-five as in 0. limacina. The branchia3 are propor- 

 tionally shorter and do not quite reach the tail. The tail 

 diverges, for it presents only a few blunt cirri dorsally and a 

 rounded median and two short lateral cirri ventrally. When 

 viewed from the rear this region shows a series of short blunt 

 cirri, about nine in number, forming an arcli over the large 

 median bluntly rounded papilla on the ventral surface. One 

 of the cirri forming the arch had a slender terminal process 

 or papilla distally, but it is uncertain whether the others had 

 such. The structure of the caudal region thus differs from 

 that of Ophelia limacina, and is not a stage in the develop- 

 ment of that form, nor does it approacli that of Ophelia 

 neglecta, Aim^ Schneider, or other form. The structure of 

 the foot is similar to that of the species just mentioned, with 

 a shorter branchial cirrus, and beneath it two tufts of simple 

 bristles. The example is a female with large ova in the 

 coelomic cavity in July. 



Even more generally distributed than Ophelia limacina is 

 the next form, viz. Ammotrypane aulogaster, H. R., which 

 ranges along both eastern and western coasts of Britain and 

 extends far north. Instead of the anterior region being devoid 

 of a groove, as in 0. limacina, in the present form the entire 

 body is deeply grooved ventrally from end to end, and the 

 setigerous region bears a single tutt of simple bristles, a large 

 dorsal cirrus (branchia) , and a small ventral cirrus. The anus 

 terminates in a scoop-shaped hood opening ventrally, and with 

 four cirri along each border, a pair of larger and rather thick 

 cirri at its base, and with a slender cirrus between them. 



A genus not hitherto known in Britain is Armandia, 

 Filippi *, an example of which was dredged amongst sandy 

 mud off one of the small islets in the Sound of Harris in 

 1872. It has been provisionally termed A. rohertiance. In 

 this the head is obtuse and rounded, somewhat like that of 

 Ammotrypanella arctica, M'l.f, marked dorsally by a con- 

 striction, whilst ventrally the prominent ridges of the ventral 

 longitudinal mu-cles leave only a small free rim at the snout. 



* Arch, per la Zool. I'Anat. e Fisolog. Genova, 1861, vol. i. p. 215. 

 t Trans. Linn. Soc. 2ncl ser. vol. i. p. 605, pi. Ixv. fig. 12. 



