140 Transactions. — Zoology. 



Art. XXI. — Notes on Aniaurobioicles maritima, Cambridge * 



By P. Goyen. 



[Read before the Otago Institute, 8th November, 1887.] 



This very interesting and handsome spider was discovered by 

 the late Dr. Smith on rocks at Allday Bay, North Otago, and 

 sent by Captain Hutton to the Rev. 0. P. Cambridge, by whom 

 it was figured and described in 1883. A mature and two im- 

 mature examples were sent to him, labelled " Marine Spiders," 

 but nothing was added to indicate in what sense they were 

 marine. I have since found this spider at Shag Point, about 

 twenty miles south of Allday Bay. It builds its nest in the 

 clefts and crannies of rocks, some of which are at full tide 

 exposed to the swell and battery of the South Pacific, and none 

 are beyond reach of the spray from the breakers. Some of the 

 nests are then completely under water. Though varying slightly 

 with the sbape of the clefts in which they are built, they are 

 generally tubular in form, and consist of web which is of a 

 leathery consistence and apparently impervious to water. The 

 tubes are from one to two inches in length. At low tide the 

 mouth is invariably open, and immediately in front of it there 

 is often spun a short loose funnel-shaped snare. After the re- 

 cession of the tide, and whilst the rocks were yet wet, I have 

 sometimes found the mouth of the nest sealed up. Perhaps they 

 are all so sealed when under water, but this is a point I have 

 been unable to determine. It seems all one to the spider 

 whether in or out of water ; for I have frequently filled a nest 

 with water, and its occupant has never shown any signs of dis- 

 comfort. Taken from its nest and placed at the edge of a pool, 

 it will, after a good deal of teasing, run down the side to the 

 bottom, and there remain till all danger seems to have dis- 

 appeared. Seen thus, its body covered with silvery globules of 

 air, it is a very handsome object. Unlike Eobsonia marina, 

 Cambridge, it does not seek its prey in the water, but lies in 

 wait at the mouth of its nest for the insects that abound on the 

 rocks, in the clefts of which it builds. It is a plucky little 

 animal, and fights very stoutly to retain possession of its nest. 



The male is smaller and of a more slender build than the 

 female, but exactly resembles her in colourations and markings. 

 His cephalothorax is more rounded at the sides and more con- 

 stricted at the caput, and his legs are longer than hers. Those 

 of the fore pair are distinctly (Hmm.) longer than those of the 

 hind pair. The male may be readily recognised from Cam- 

 bridge's excellent figure of the female. 



New Zealand is, I believe, the only country in which spiders 

 have been found inhabiting the sea. 



* Proc. Zool. Soc, June, 1883, PI. xxxvi., tig. 3. 



