Kramek. — Pelagic Copepods and Cladoceres of Auckland. 215 



almost nothing has yet heen published on the pelagic Copepods 

 and Cladoceres, I will not delay giving a report. 



What is known of the Copepods of New Zealand is contained 

 in a treatise by G. M. Thomson, of Dunedin, published in 

 vol. xv. of the Transactions ; but, because his collections are 

 " from rock-pools or shore-kelp " of the Otago Harbour, they 

 include little beside the Harpacticidas, which, with a few ex- 

 ceptions, belong to the littoral and not to the pelagic fauna. 



The word "plankton" is now commonly adopted for 

 " pelagic moulder," or " auftrieb." It means the small (micro- 

 scopical) organisms floating in the sea or in a lake ; and 

 "pelagic plankton" would mean those floating free from the 

 coast and from the bottom. The Copepods, these small crus- 

 taceans, are the most important, and never-wanting, part of 

 the plankton. 



On the volumetric draughts I shall report later, when the 

 material is worked out. It is found that the plankton contains 

 more species and much more individuals in the Hauraki Gulf 

 (and in Waitemata Harbour) than in the open sea, as, for 

 instance, outside Great Barrier Island. 



Dana, in the publications of the United States Exploring 

 Expedition, has named only four Copepods as found in the 

 neighbourhood of New Zealand. Giesbrecht, in his excellent 

 work on the Copepods ("Fauna und Flora des Golfes von 

 Neapel," vol. xix.), which is also the newest and most funda- 

 mental one, including all that was known about the order up 

 to 1892, says, on these four species, that the names of three 

 must be changed, following the priority of authorship. 



1. Pontella valida, Dana, is not a Pontella ; but the genus 

 cannot be recognized from Dana's description. 



2. Pontellina simplex, Dana, is not a Pontellina, but a 

 Labidocera. 



3. Miracia gracilis, Dana, is now commonly known as 

 Setella gracilis, Dana. 



The fourth, Sapldrina gemma, Dana, retains the name 

 given by Dana. Setella (Miracia) and Saphirina seem to 

 belong principally to the open sea. I found Setella near 

 the Kermadec Islands, but never in the harbour. A Pontella 

 has recently been found by Thomson in the Otago Harbour, 

 and one species of Labidocera in the Hauraki Gulf. 



Of all the Copepods recorded from the Pacific Ocean 

 anywhere near New Zealand, I have only found two in the 

 Hauraki Gulf — the widespread and common Paracalanus 

 parvus, Claus, and Clausocalanus arcuicornis, Dana. Eiiterpe 

 acutifrons, Dana, which is invariably present in the gulf, in 

 the Pacific has only been found in long. 108° W. and lat. 

 20° S., near Easter Island. All the other Copepods named 

 below are quite new for the Pacific, and therefore also 



