of the North Atlantic and of North- Western Europe. 671 



the length of the second; last joint minute: second, third, and fourth joints 

 with one ringed and plumose seta on the upper margin, the second with two very- 

 minute spinules on lower margin, the third with one, and the fourth with two 

 distal, long, ringed, and plumose setse; penultimate joint with two minute setae on 

 the upper part of the extremity, and one long-ringed seta on the lower corner ; 

 last joint with five setse of nearly equal length, two of which are of very 

 remarkable structure, apparently membranaceous and flattened, being very closely 

 and minutely wrinkled on every part, and (fig. 3 a) wholly destitute of cilia or other 

 appendages. Antennae with basal joint smaller than usual; swimming-branch 

 nine- jointed, the last joint minute, with only two setae, one of which is very 

 small ; nine setae in all ; no appendicular branch (fig. 4), but in the place usually 

 occupied by it there is a very large-ringed plumose seta, near the origin of which 

 are three very small, but distinctly ringed setse. 



The mandible has the basal joint furnished with a long masticating palp (fig. 

 5), cleft at the extremity for a short distance, and there hirsute ; first joint of palp 

 without masticating s]Dines but with fascicles of very minute cilia on the side ; 

 inner margin with four setae, two of which are small but ringed, the other large, 

 ringed, and densely plumose, outer margin on the distal half with one long- 

 ringed ciliated seta, followed by a pair of similar setae, and at the extremity a 

 well- developed laminar appendage, which is nearly two-thirds the length of the 

 following joint, and ends in two setae ; second joint equal in length to about 

 two-thirds of the first, with only one seta on inner, and none on outer margin ; 

 third joint more than half as long again as the second, inner margin with three 

 series of minute cilia, followed by a spine, and then a pair of spines, outer 

 margin with a fascicle of three or four setae at the middle ; last joint minute, 

 bearing remarkably long and slender well-curved ungues, which exceed in length 

 the two preceding joints, and below the ungues are two setae. 



First maxillae (figs. 6, 6a) very short, with three lobes, the upper ending in 

 three spines of remarkable character and a seta, the second in two spines and two 

 setae, the third is furnished with four setae, the apical spines of the first two lobes 

 have a spine-like process near the extremity of their outer side, the inner side in 

 one case has the latter half very delicately serrated, in another case the lower half 

 of the margin bears five or six spinules, and the distal half is finely ciliated ; the 

 distal margin of the lobe-bearing joint has a very large plumose seta below, a 

 f aside of three smaller setae half-way up, and a large plumose seta above ; the 

 following joint has one seta on the upjaer margin, and one near the infero-postea- 

 corner ; the last joint bears a long slender unguis and three or four setae. 



In our dissection of the second maxillae (fig. 7) we are unable to find any lobes 

 or seta anterior to the teeth. There are two teeth. The outer of these (fig. 8) is 

 of enormous size and consists of an irregularly oblong plate, or jaw, laid 



5B2 



