386 
Proceedings of the Royal Society 
In the course of these experiments the action of iodacetic ether 
upon sulphide of methyl was studied. The reaction here takes a 
different course, iodide of trimethyl-sulphine being produced in 
large quantity. 
3. On a New Example of the Opheliidse (Linotrypane 
apogon )* from Shetland. By W. C. M £ Intosh. 
This peculiar iridescent pinkish Annelid was dredged in 1871 
in Bressay Sound, in four or five fathoms, on a bottom of coarse 
sand and gravel, which abounded with finely-branched Melobesia 
calcarea, Ell. and Soland. 
The form resembled an active nematoid worm, being elongated, 
nearly cylindrical throughout the greater part of its length, and 
devoid of bristles or lateral projections. It progressed in the most 
vigorous and spasmodic manner, by twisting or thrusting itself 
through the sand, after the mode of Ammotrypane, or a most rapid 
eel-like fish. Moreover, the slightest interference caused it to 
break in pieces, so that not a single specimen out of the whole 
series remains entire, though every precaution was taken to im- 
merse the animals in spirit on removal from the dredge. The 
activity and purpose displayed by the species are diagnostic when 
compared even with the most nimble of the nematoid group, so 
that no difficulty is experienced in distinguishing it. 
The Annelid reaches the length of three or four inches, and is 
only about a millimetre (^th inch) in diameter. The body is 
rounded, slightly tapered in front, where the pinkish colour is best 
marked, and richly iridescent, even to a greater degree than either 
Ammotrypane or Ophelia. The head terminates in a rounded ante- 
rior border, from which two short clavate processes project. The 
latter have a very thin investment of the hyaline cuticle, with a thick 
layer of granular cells (hypoderm) beneath. Some longitudinal fibres 
occur at the base, but the contractility of the organs is limited. 
Two eyes, consisting of encapsulated masses of black pigment, are 
situated near the dorsal surface of the tissues of the snout. 
* Xivev, a thread, and r^vrdvyi ; the specific name from u-Truyuv, beardless 
