of the Fishery Board for Scotland. 



149 



any hinge. The fifth feet are three-jointed, the last joint having four 

 spines, two long and two short. 



The spines of the ordinary swimming feet are long, and finely serrated 

 on the inner border. They have no hairs, but have two secondary spines 

 at their bases. 



The caudal segments are extremely long and slender, and each segment 

 carries two short spines. The terminal setae are plumose, but not quite so 

 long as the caudal segments. Although one of the commonest of marine 

 copepods, it was not found in such abundance as some of the other 

 forms; it was, however, obtained in small numbers all through the 

 season. 



Centropages typicus (Kroyer). — It is very like G. hamatus, the differences 

 being most marked in that C. typiciLs has the antennae more robust and 

 with a tooth on the outer margin of the first, second, and fifth joints. 

 The terminal spines of its swimming feet are more slender, and finely 

 serrated, and each carrries two secondary spines, whereas the terminal 

 spines of C. hamatus are coarse, the teeth set apart, and there is only one 

 secondary spine. 



In C. typicus the last thoracic segment is produced downwards on each 

 side into a strong spine. On the first segment of the abdomen there are 

 three plumose spines, and the tail setae, which are five in number, are 

 also plumose. In colour it is brown. It was tolerably plentiful. 



Dactylopjus tishoides is a small, graceful copepod, with an elongated 

 body and a head produced into a short, conical rostrum. The antennae are 

 nine-jointed and taper gradually off from base to apex. In the male the 

 rigid antennae are hinged between the sixth and seventh joints. The fifth 

 pair of feet are very small and consist of two flattened pieces of a some- 

 what triangular shape, with strong marginal setae. In the female the 

 antennae are more densely setose than those of the male, and of course 

 want the swellings consequent upon the hinge in the male organ. The 

 fifth pair of feet consist of two broad ovate plates v/ith long setae on their 

 outer margins ; like the corresponding feet in the male they are small and 

 insignificant. The feet generally are densely setose and spinous, and 

 having the inner branches longer than the outer. The abdomen and caudal 

 segments are short but well proportioned, and the tail setae are very long. 

 This copepod is found widely distributed, living both on the surface and 

 at considerable depths ; a variety also lives in the brackish water near 

 mouths of rivers, etc. In colour it is of a rich brown. 



Centropages hamatus (Lilljeborg). In many respects it is similar to 

 the preceding copepod, but is still more like C. typicus. The body is 

 slender and elongated, with the anterior antennae twenty-three-jointed, 

 the right male antenna is hinged between the eighteenth and nine- 

 teenth joints. There are strong-pointed teeth on the outer margins of the 

 first, second, and fifth joints. 



In the male the fifth pair of feet are adapted for swimming like the 

 others but the outer branch of the right limb has the last two joints 

 developed into a grasping organ. 



In the female the fifth pair of feet are similar to the others. 



The spines of the swimming feet are long and straight, the teeth being 

 much coarser and set further apart than they are in C. typicus, by which 

 arrangement these two forms are perhaps most readily distinguished. This 

 form was tolerably plentiful. 



Parapontella hrevicornis (Lubbock). — The rostrum is forked and the 

 head separate from the thorax. Anterior antennae eighteen-jointed, each 

 joint having a few short hairs, and the first, eleventh, thirteenth, and 

 sixteenth have long setae. The right male antenna is peculiar ; it has 



