——=— 
oe i eel > ee al 
of the Fishery Board for Scotland. 261 
appears to be composed of two or three coalesced joints, as shown in the 
formula, which gives approximately the proportional lengths of the 
joints :— 
Op Gloe tO 4) G10 “12 * 16.°9.°9'° 16°12 "12°12 °12*+16 18° 8 *:26° 
1° emer ero G7 8" Os 10 El 1213 14 Wh 16 1 
' Mandibles stylet-shaped, stout, and elongate. The mandible-palp consists 
of a single oblong joint, the length of which is greater than twice the 
breadth ; and three stout, moderately long and nearly equal sete spring 
from its truncate apex. The maxille are composed of a sub-triangular 
primary part, furnished with three apical sete, and a narrow cylindrical 
secondary part, provided with four setz at the apex. The anterior foot- 
jaws have the basal part stout, but the end is slender and curved, and 
forms a claw-like appendage. The posterior foot-jaws and swimming-feet 
are somewhat like those of Dermatomyzon nigripes (Brady and Robertson). 
The fifth pair are simple and two-jointed. The first joint is short, and its 
breadth is about equal to twice the length, and a seta springs from its 
- upper distal angle. The second joint is longer and narrower, the length 
being about twice the breadth. It is furnished with two apical sete. 
The caudal stylets are nearly as long as broad, and are equal to the com- 
bined lengths of the last two abdominal segments. 
Habitat.—Vicinity of the Bass Rock. Rare. 
The very tumid form of the cephalo-thorax and short abdomen give to 
this species a very curious and striking appearance that at once dis- 
tinguishes it from all other Copepods known to us. 
Genus Acontiophorus, Brady (1880). 
Acontiophorus elongatus, T. and A. Scott. 
1894. Acontiophorus elongatus, T. ani A. Scott (31), p. 145, pl. 
ix. figs. 15-20. 
Description.—Female. Length, 1 mm. (4 of an inch). This is an 
elongateform. The abdomen is slender, and equal to about two-thirds of 
the length of the cephalo-thorax. The anterior antenne are slender, and 
composed of seventeen joints. The proportional lengths are as follow :— 
mee be b2)° 15-* 15.2 Ba Eee Fa ds 
so! oS 6 
ae oe 10 TT? < 18 14 * To 16 ee 
. ° 6 
oe a AT 
Posterior antenns and mouth organs are nearly as in Acontiophorus 
scutatus (Brady and Robertson). The mandibles are extremely long and 
slender, being about equal in length to the elongate siphon. Foot- 
jaws and swimming-feet also somewhat similar to those of Acontio- 
phorus scutatus, but the fourth pair are armed with remarkably broad and 
stout dagger-shaped spines on the exterior margins of the outer branches, 
and broad sabre-like terminal spines on both branches. The fifth pair 
consists each of a single elliptical joint, furnished with three apical sete. 
- Caudal stylets very short. 
Habitat.—Vicinity of the Rock. Frequent. 
Remarks.—The slender form of this species, and especially of its 
elongate and slender abdomen, enables this species to be distinguished 
from any other described <Aconteophorus. It differs from the typical 
Acontiophorus scutatus in the posterior antennee having only one long and 
slender spine at the apex instead of two lancet-shaped apical spines, but 
otherwise the species now described is a true Acontiophorus. 
