Some New or Inttle Known Oligocheta. 45 
cells converge and perforate the longitudinal layer of the 
body wall; arrived at the epidermis, they spread out into a 
disc-shaped area, contrasting with the surrounding epidermis. 
This area appears to be composed of smaller pear-shaped 
cells, in other respects like those of the deeper lying organ. 
In front of and behind each of these papilla is a nerve arising 
from ventral cord, and penetrating the body wall. A cursory 
glance at these organs would undoubtedly lead to the infer- 
ence that they were glandular bodies, serving perhaps as 
organs of adhesion during coitus; the prevalence of such 
organs among the Oligocheta would support this view of 
their nature. Their relations, however, to the nerve cord 
(their enclosure within its sheath, and the absence of any 
breach between their cells and those of the nerve cord) seem 
to indicate that they are specialised regions of the nerve cord 
connected with integumental sense organs. In this case 
they will in all probability be comparable to the “ wing-like 
processes” which occur in several places upon the nerve 
cord of Pachydrilus nervosus, and one or two other species 
of Pachydrilus. The presence of these structures seems to 
distinguish the present species of Fridericia from any other 
that has been hitherto described. 
VI. The Land and Fresh-Water Crustacea of the District 
around Edinburgh. Part Il—The Ostracoda and 
Copepoda. By Tuomas Scort, Esq., F.L.S., Cor. Mem. 
Glas. Geol. Soc. and Nat. Hist. Soc. of Glasgow. 
(Read 19th April 1893. ) 
In a previous communication I gave a short account of the 
land and fresh-water Amphipoda and Isopoda of the Edinburgh 
district; in this paper I propose to notice two of the groups 
of the Entomostraca, viz., the Ostracoda and Copepoda. I 
intended to have given an account of these groups during 
the previous session of the Royal Physical Society, but want 
of time compelled me, reluctantly, to delay doing so till a 
more convenient season. One of the chief difficulties in 
dealing with the larger or “higher” Crustacea is to find the 
specimens, but the chief difficulty with the micro-forms— 
