402 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



tion, and lias been recorded from the Faroe Channel, 

 Atlantic and Pacific Oceans, and from the Mediterranean. 



Rhincalanus cornutus (Dana). 

 Occurrence, No. 6. A night gathering. 



This species is easily recognised by its projecting fore- 

 head, and is usually not nearly so rare in tropical 

 plankton as R. nasutus. Its distribution is also more 

 extensive. 



Paracalanus aculeatus, Giesbrecht. 

 Occurrence, Nos. 2, 4. Night gatherings. 



This Paracalanus is not unlike the next species, but is 

 easily distinguished from it by the structure of the female 

 fifth pair of feet. It has already been recorded from the 

 Indian, Atlantic and Pacific Oceans, and also from the 

 Mediterranean. 



Paracalanus parvus (Claus) . 

 Occurrence, Eos. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 16, 17. 

 This species has practically a world-wide distribution. 



Acrocalanus gibber, Giesbrecht. 

 Occurrence, Nos. 4, 5, 6, 7, 8, 9, 12, 15, 16, 19. 



This species resembles Paracalanus in size, but is dis- 

 tinguished from that genus by the fifth pair of feet in the 

 female being very rudimentary or wanting altogether. It 

 is widely distributed in tropical and sub-tropical regions. 



Calocalanus pavo (Dana). 

 Occurrence, Nos. 2, 3, 4, 6, 7, 12, 13, 16, 18. 



Perfect specimens of this species, which is so well 

 illustrated by Dr. Giesbrecht, are very rarely obtained in 

 collections taken by the ship's pump, the beautiful caudal 

 setaB, as a rule, are broken off, and also the long setse on 

 the antennules. The species is easily identified, however, 

 when the caudal furca alone are present; they project at 



