302 The Irish Naturalist. 



for the American species. But did our Tanystyhim conirostrCy 

 or its less-modified ancestors come northwards along the west 

 coast of Africa to the Mediterranean and to our shores ? The 

 general southern range of the genus stronglj^ suggests such an 

 explanation, as no Tanystylnvi is known from the Norwegian 

 or other north European coast. On the other hand there can 

 be no doubt that T. conirostrc is very closely allied to the 

 North American T. orbiadare, a consideration which renders 

 it at least possible that the migration to Europe may have 

 taken place eastwards along an old shore-line to the north of 

 the North Atlantic. On such a view, we must regard the 

 newi}' discovered Irish station as a mark of the path b}^ which 

 our pycnogon travelled to its Mediterranean home. In all 

 these speculations, however, it must be borne in mind how in- 

 complete our knowledge of the range of these animals still is. 

 While such theories add zest and interest to the investigation 

 of our fauna, new facts will surely be brought to light which 

 will oblige us to modify them. If zoological science is to 

 progress there must ever be an evolution in the thoughts of 

 its students, as we believe there has been and is in the 

 wonderful creatures which it is their pleasure to study. 



EXPI^ANATION OF P1.ATE 6. 



Fig. I. Tanystyhim conirostre (Doliru), natural size. 

 „ 2. „ ,, adult male, magnitied. All limbs 



removed except clielifori {a), 

 and tlie right palp and third 

 walking leg. 



,, eye-eminence in profile mag- 



nified. 



,, palp, highly magnified ; (a) open- 



ing of excretory gland. 



,, false leg of male, highly mag- 



nified. (In this figure, spine 

 at tip of ninth joint should 

 have been shown projecting 

 beyond end of tenth joint). 



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