86 THE ROYAL SOCIETY OF CANADA 
constriction occurs between the 8th and 9th joints and the succeeding 
joints become gradually longer and up to about the 14th and 15th 
gradually wider also, the width of the limb at this region being about 
twice what it was at the constriction between the 8th and 9th joints. 
The 18th and 19th joints are at least twice the length of the 17th and the 
19th bears upon its outer distal border a spine-like prolongation almost 
as long as the 20th joint; the middle dilatation may be regarded as 
ceasing with the 19th joint, and beyond this there are six joints forming 
the terminal portion of the limb, the last of them, the 25th, being very 
small, but distinctly separated from the preceding one. There is no 
angulation and no denticulate grasping lamellæ were present on any 
of the joints. 

Fig. 12. Right first antenna of Paralabidocera amphitrites © 
The last thoracic segment is asymmetrical, its left lateral lobe 
resembling that of the female, while on the right side it is prolonged 
backwards as a pointed process that reaches to about the middle of 
the first abdominal segment. The fifth thoracic limbs (fig. 13) are 
also asymmetrical to the extent that one is longer than the other and 
terminates in three sharp points, while the other has only two smaller 
terminal points. Both consist of but one single-jointed ramus and 
there is no indication of the chelate condition occurring in Labidocera. 
The abdomen consists of four segments, (fig. 14) the first being 
slightly asymmetrical. The furcal rami are symmetrical and setose 
on their medial borders; their length is twice their greatest breadth. 
4. The fourth patch of “brown water’’ examined, was encount- 
ered off the Escalente Rocks, Nootka Sound, Vancouver Island, and 
its constituents are for the most part identical with forms described 
from patches 3 and 2. Coscinodiscus nobilis was rare, Ceratium fusus 
frequent, and C. furca occasional, but there was by no means so great 
a variety of protophytic forms as was seen in the other patches. 
The medusa, Rathkea blumenbachii, was again present in considerable 
numbers, and Diphyes appendiculata was represented by a few examples 
as was also the Brachiolarian larva observed in patch 2. The Crus- 
tacea, as usual, were well represented; Evadne Nordmanni was observed 
and more rarely Podon (species undetermined). Of the Copepoda, 
