of Edinburgh, Session 1870 - 71 . 
439 
of the structural, or other, peculiarities, of the remarkable Nemer- 
teans and Annelids found in this expedition, and of certain in¬ 
teresting questions in zoology connected therewith. 
Amongst the Nemerteans is the curious Ommatoplea spectabilis of 
De Quatrefages, a species of much interest, in so far as its discoverer 
stated that it was furnished with a peculiar horny pectinated 
structure in its proboscis. Careful examination showed that the 
latter has a strictly Ommatoplean anatomy, the longitudinal bands 
of the reticulated layer of the pinkish organ being very apparent. 
In Prosorhochmus claparedii , Keferstein, the granules of the exter¬ 
nal circlet of glands round the stylet-region of the proboscis are 
unusually large and distinct. The granular basal sac of the central 
stylet is of a peculiar shape, having a straight border and sharp 
angles posteriorly, and obtuse angles at the sides anteriorly. 
The pale setting of this apparatus is comparatively limited in bulk ; 
and the curved fibres of the region behind the latter pass out¬ 
wards and forwards in a very distinct manner. The development 
of the ova in the bodies of the females of this viviparous species is 
very similar to that of the free ova and their products in other 
Ommatopleans, space being formed for the growing embryos by the 
enormous dilatation of the ovisacs. Indeed, the larger young speci¬ 
mens, which are often doubled within the body of the parent, 
appear to be in cavities produced by the coalescing of many ovisacs ; 
at any rate, it is clear that to describe them, as former authors have 
done, as simply within the body-cavity of the worm, is wanting 
in structural accuracy. It seems to be a further stage of the type 
of development observed in Nemertes carcinophilus, Kolliker 
[Folia involuta , Van Beneden), in which, after the deposition of 
the majority, a few are left in the body of the parent for subse¬ 
quent evolution. A still more remarkable Nemertean is the 
Borlasia elisabethce, M‘I., from Herm, a large species with a 
pointed, eyeless snout. In this form the powerful muscular layers 
of the body-wall are tinted of a fine reddish hue, so that the 
resemblance in this respect to the muscles of the higher animals is 
striking. The proboscis is extremely slender in proportion to the 
bulk of the animal, and its muscular walls are comparatively thin. 
A reddish coloration was frequently observed in the living animal 
at the white belts, showing that some contained fluid tinted the 
