16 124 Proceedings of the UoyaX IrUh Academy. 



proved to be Acrothrix mirdbilis, The plants are Indistinguishable in the 

 field, but with microscope the greater length of the peripheral filaments of 

 the presenl plant are at once noticeable. Pound floating near Achill Bridge 

 and al Old Head, September, 1011. 



Acrothrix mirabilis Kylin (07, p. 93). 



The specimens on microscopic examination were ;tt lirst determined us 

 Meeogloia neglecta Batters, with which they agree closely ; butDr. Kuckuck 

 informs me that they are identical with A. mvrdbilis Kylin, authentic 

 material of which he has seen. Kylin's genus is based on a good character, 

 ;uk1 should be maintained ; but if the two plants are synonymous, Batters' 

 specific name should be employed, as he first detected and published the 

 species (Journ. Bot., 1000, p. _!). A. difficulty, however, presents itself, since 

 bhe type of M. neglecta cannot be found in the Hatters collection, and hence it 

 is impossible to re-examine the points in which the Clew Bay material differs 

 Prom the description. The discrepancies are trivial, hut until we are certain 

 that all the Mesogloiae of our .shores are known, it seems wiser to let M, neglecta 

 .stand as a separate Bpecies, and not to link it with A. mirabilie, 



The present plant hears a striking resemblance to M. OriffUlmana, and 

 \va« assumed to be such on oollecl ing, It is remarkable also that it was found 

 in practically the same Localities. Four plants in all were taken, two at Old 

 Head and two at Achill Sound, July, 1010. 



Leathesia crispa llarv. 



A few specimens of L. crispa were collected during the first trip bo Clare 

 Island, but on no subsequent viait. In Journ. 13ot., xlvi, p. 329, I have 

 dealt with the synonymy and distribution of this species. 



Fucus ceranoides L. 



invariably present where fresh-water streams occur on sheltered shores. 

 (See pp. 83-88.) 



F. spiralis L. 



For remarks on the various forms assumed by this speoies see Fucaceae 

 associations (pp. 23 and 51). One variety, however, requires special notice. 



Yar. nanus Stackh. — In many spots in Achill Sound, the sheltered form 

 of var. nouns \k found growing on vertical peat-banks at high-water mark. 

 An unbroken series may at times be traced from bhe normal form. The 

 plants measure I I inches in Length, are slightly (1 3 times) branched, and 

 i'lmi freely al bhe proper season. In many of the receptacles examined 

 the OOgonia were unripe (May); hut they appeared to he perfectly healthy 



