Adams — A Spiojjsis of Ins h Algcv, Freshwater and Marine. 53 



Sterrocolax 



decipiens ScJim. M L C U 

 Trailliella 



intricata Batt. L. 



VI. — Makine Ehodophyce^ — continued. 



Doubtful Species. 



Callithamnion 



lanuginosum Lyngb. Ireland 



Summary of Distrihution. — The number of marine species found in each 

 of the four provinces and in the whole of Ireland is indicated in the 



following table : — 





M 



L 



C 



U 



Ireland 



Peridiniese, .... 







7 











7 



Diatomacese, .... 



114 



249 



171 



92 



377 



Cyanophyceae, 



16 



28 



7 



10 



31 



Chlorophycea3, 



47 



52 



27 



43 



79 



Phseopliycese, 



86 



75 



64 



69 



120 



RhodophyceEE, 



Total, 



167 



165 



126 



160 



229 



430 



576 



395 



374 



843 



General Remarks on Distribution. — Ten species have been found on the 

 Irish coast that are not so far known to occur in Great Britain. The local 

 distribution of these is as follows : — Chmtomorplia crassa Kiitz., in ditches 

 by the North Wall, Dublin, and at Achill Island ; Cladapliora Macallana 

 Harv., at Koundstone and in Co. Cork ; Goclium elongatwii Ag., at Kilkee ; 

 Fucus anceps Harv. and Ward, at Kilkee ; Litosiphon hihernicus Batt., at 

 Kilkee ; Hahjmenia latifolia Crn,, at Blackhead ; Lithopihyllum dentatum 

 FosL, at Eoundstone ; Clathromorphum circumscriptum FosL, on the west 

 coast ; Lithothamnion Stroemfeltii FosL, common in Ireland ; Corallina virgata 

 Zan., at Bangor, County Down. 



A considerable number of species characteristic of the warmer regions 

 of the Atlantic or of the Mediterranean have been found on the south 

 or extending up the west coast. These are Cladapliora cornea Kiitz., 

 C. corynarthra Kiitz., Padina piavonia Gaillon, Dictyopteris memhranacea 

 Batt., Seirospora interriqjta Schm., Helminthocladia Hudsoni J. Ag., 

 Halopitliys incurvus Batt., Pterosiphonia complanata Schm. 



HalosphcBra viridis Schm., a native of warm seas, occurs in the plankton 

 of the west coast. Probably all these species owe their presence on the 

 Irish coast to the influence of the Gulf Stream. 



[F-] 



