31 NEW AND RARE SPECIES OF COPEPODA FROM SCOTLAND 
thirds of their entire width across the broadest part; the 
secondary branches are very small, obscurely triangular in out- 
line, and furnished each with three small setze on the outer edge 
(Fig. 12). The caudal stylets are in the form of elongate- 
ovate lamelle; in length they are equal to both the last two 
abdominal segments together, and their breadth is about 
equal to two-thirds of their length; they are also each fur- 
nished with four terminal setz, the principal seta being about 
twice the length of the stylets, but the others are very small. 
Ovisac small, containing a number of moderately large ova. 
Male—TVhe male is similar to the female, except in the 
following particulars :—The anterior antennz are each six- 
jointed ; the last four joints are modified and hinged, and 
form powerful grasping organs. The basal joints of the 
fifth pair of thoracic feet are coalescent, as in the female, but 
are much shorter, being only about half the length; the 
sixth pair of appendages are foliaceous, broadly subtriangular 
in outline, and not coalescent (Fig. 13). 
ffabitat——In pools near low water on the shore of the 
Firth of Forth, at Musselburgh ; rather rare. 
Remarks.—This species is at once distinguished from 
any others of the same genus by the large, lamelliform 
caudal stylets, and by the form of the fifth pair of thoracic 
feet, as also by the structure of the anterior antennez. We 
have much pleasure in giving to this species the name of our 
kind friend Mr. David Robertson of Millport, the veteran 
Scottish Naturalist, who was one of the first to introduce us 
to that most interesting study—the study of the Micro- 
crustacea. 
LEPTOPSYLLUS MINOR, sf: wov: (Plate Il. Figss 15-22% 
Description.—Female—Length, -46 mm. (,, of an inch). 
Body elongate, very slender. Anterior aiteunes short, 
moderately stout, seven-jointed, somewhat similar in structure 
to those of Leptopsyllus robertsonz. ‘The proportional lengths of 
the joints are shown by the formula—- 
Proportional length of joints 20 14 ti. 7h 
Number of the joints I 2) 3° Bo 5 Somme 
