242 Transactions. — Zoology, 



Art. XIII. — On the New Zealand Pycnogonida, with Descriptions of new Species. 

 By Geo. M. Thomson, F.L.S. 

 [Bead before the Otago Institute, 1th May and 13th November, 1883.] 

 Plates XIV-XVI. 

 The Pycnogonida form one of the many groups of animals in the New 

 Zealand fauna of which very little is yet known. This is not however to 

 be wondered at, when we consider of how fragmentary a nature the litera- 

 ture of the subject is, and how imperfect our knowledge of the whole group 

 is. Two noteworthy works have however recently appeared, which bring 

 pretty fully together all that is yet known, and at the same time add greatly 

 to the general fund of information. These are " The Eeport on the Pycno- 

 gonida dredged by H.M.S. Challenger," by Dr. P. P. C. Hoek of Leiden, 

 and " Die Pantopoden des Golfes von Neapel," by Dr. Auton Dohrn, both 

 beautifully illustrated. Both works appeared in 1881, but quite indepen- 

 dently of one another ; and while Dr. Dohrn's work is much the most 

 complete in anatomical detail, it does not help us much in the systematic 

 portion, as the species described are only those new to science which came 

 under the author's observation while working at Naples. 



In Dr. Hoek's report a catalogue of all the known species of Pycnogonida 

 is given, and from it we learn that the following species only have been 

 found in the New Zealand seas. 



1. Nymphon compactum, Hoek.* 



2. ,, longicoxa, Hoek.* 



both dredged from a depth of 1,100 fathoms at a station east of Auckland. 



3. Oorhynchus ancklandia, Hoek,* dredged from a depth of 700 fathoms 

 east of Auckland. 



In the New Zealand Journal of Science, vol. i., p. 28, I recorded the 

 occurrence of Ammothea pycnogonides, Nob., as common along the East 

 Coast of Otago, but the description of that species is so unsatisfactory, and 

 would apply to so many species of Ammothea, that I have re-described it 

 provisionally as A. dohmi, and figured it. 



I am convinced that a close examination of our seas at moderate 

 depths would reveal a considerable number of new forms, and that 

 the apparent absence of them is chiefly due to their having been over- 

 looked. 



In describing the accompanying new species, I need make no apology 

 for giving the characters of the genera, and placing in order all the species 

 now known. 



* See N.Z. Journal of Science, vol. i., p. 170-172. 



