ALGJE 01? WEST IRELAND. 173 



Long, sine acul. 27-30 11 ; lat. sine acul. 17-20 li; long. acul. 



30-38 p ; lat. isthm. 7-7'5 li. 

 II. Lough G-uitane. 



ifi 



which British species it nearest approaches, the convex sides of the 

 end view and the different insertion of the spines being alone suffi- 

 feient to distinguish it. From S. Lewisii, "Wood, it differs in the 

 absence of the small spines from the straight sides of the front 

 view of the more triangular semicells. 



13. Stattbastbum megacanthum, Lund. {Desm. Suec. p. Gl, 

 tab. 4. fig. 1.) 



I. Lakes, Clif den to Eoundstone ; Ballynahinch. 



tl4. S. bacillare, Breh. in Balfs, Brit. Desm. p. 211, tab. 35. 

 fig. 21. 



Long. 25 li ; lat. 33 li ; lat. isthm. 7 li. 



I. Lough Aunierin. 



* 



Tar. obesum, Lund. {Desm. Suec. p. 57, tab. 3. fig. 24.) 



II. Adrigole. 



15. S. LT7XATTIM, Balfs. (Brit. Desm. p. 124, tab. 34. fig. 12.) 

 Long, sine spin. 25 fi ; lat. sine spin. 30 fi ; lat. cum spin. 36 /* ; 

 lat. isthm. 12-5 /i . 



I. Derryclare Lough ; Oorid Lough. — II. Near Lough Brin. 



Infi 



) 



Long. 40 n ; lat. (cum spin.) 45-46 p. ; lat. isthm. 22'5 p. 



I. Lakes, Clifden to Eoundstone. —II. Glengarriff; Carranluo- 

 hill. 



17. 8. OLiGACAJffTHUM, Breh., ttvar. incisum, nov. var. 

 (PI. XXII. fig. 17.) 



Semicellulae marginibus lateralibus inferioribus incisis ; a ver- 

 tical visae triangulatse, lateribus leviter convexis. 



Long. 39 p ; lat. 40 fi ; lat. isthm. 225 fi. 



I. Lakes, Clifden to Eoundstone. 



tl8. S. megalonotum, Nord. (Desm. Arct. tab. 8. fig. 38), 



) 



8) 



