236 Part III. — Twelfth Annual Report 



in the male dissimilar, and forming powerful grasping organs. The 

 mandible-palp is comparatively small. One of the most prominent 

 characters of this family is the structure of the anterior antennae. The 

 most careful observation failed to show any difference between the male 

 right antenna and the left, and both were similar to those of the female. 

 In my paper on the Forth Fauna, published in Part III. of the Eleventh 

 Annual Report of the Fishery Board for Scotland, two species of 

 Copepoda were described, for which it was considered necessary to 

 institute a new genus {Pseudocyclopia). This new genus was placed 

 in the family Misophriidce, Brady, because of its closer affinity with that 

 family than with the family Calanidse. A further study of the characters 

 of the genus has, however, led me to the conclusion that its position in 

 the family Misophriidse, is untenable ; and as there is no other family in 

 which it can satisfactorily be included, I propose to constitute the family 

 Pseudocyclopiidce for its reception ; and I do so with the greater con- 

 fidence, as another species, now to be described, has recently been dis- 

 covered, possessing all the more prominent characters that distinguish 

 the two already described. Dr W. Giesbrecht, in his memoir ' Mitt- 

 ' heilungen iiber Copepoden ' (Abdruck aus den Mittheilungen aus der 

 Zoologischen Station zu Neapel, ii. Band 1.2. Heft), also refers to some 

 of the peculiar characters of the two described species, and to the 

 difference between them and those that constitute the family Misophriidce. 



Genus Pseudocyclopia, T. Scott (1892). 



Pseudocyclopia caudata, sp. n. (PL V. figs. 1-8.) 



Female. Like Pseudocyclopia crassicomis, T. Scott, in general appear- 

 ance and dimension. Length, # 65 mm, (55-th of an inch). Anterior antennae 

 seventeen-jointed. Basal joint very large, the others small; the second to 

 the fifth gradually decrease in size, the sixth is rather longer than that 

 which preceeds or follows, while the ante-penultimate joint is more 

 elongate than any of the others except the basal joint. The formula 

 shows approximately the proportional lengths of all the joints : — 



29 ' 8 • 7 • 5 ■ 4 ' 7 ' 5 ■ 8 • 6 • 9 • 7 ■ 7 '8 ' 10 ■ 16 ' 9 • 12 • 

 1 • 2 * 3 • 4 ' 5 ' 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 ' 



The posterior antennae, mouth organs, and first and second swimming- 

 feet are somewhat similar to those of Pseudocyclopia crassicornis. The 

 basal spines of the third pair of swimming-feet, which reach to near the 

 extremity of the outer branches, are very stout, and with the distal end 

 boldly curved — the basal spines, very like those of Pseudocyclopia minor, 

 T. Scott. The fifth pair are somewhat more robust than those of the 

 females of the two described species,, and are each armed with three 

 stout sub-equal and setose terminal spines. The caudal stylets are nearly 

 equal to the combined length of the last two abdominal segments, as 

 shown in the accompanying figures. 



Habitat. — Off St Monans. Scarce. 



Remarks. — Pseudocyclopia caudata is similar in its general appearance 

 to the two species already described ; but is readily distinguished from 

 both, even without dissection, by the comparatively elongate caudal 

 stylets. The difference in the proportional lengths of the joints of the 

 anterior antennae, and in the structure of the third and fifth pairs of 

 thoracic feet between this and the other two species, is also of sufficient 

 importance for diagnostic purposes. 



