422 Scientific Proceedings^ Royal Dublin Society. 



morphological details in the various species I have had the oppor- 

 tunity of examining. As will be seen from the annexed detailed 

 descriptions, every form, from the simplest to the most complex, 

 are met with, and they are often correlated with more or less 

 irregularity in the surface of the pollen grains. In the following 

 pages the word multicellular is taken as meaning composed of 

 many rows of cells, forming a mass of parenchyma ; and pluricel- 

 lular as designating a row of cells such as would he produced by 

 transverse septa, formed in one long, more or less cylindrical, cell. 



I hope, ere long, to have the honour of submitting to the 

 Society some further details on the subject, as well as possibly on 

 gynoecial hairs. 



As to their morphology, we may group the various forms thus : — 



(a) Simple unicellular hairs, with smooth surface, more or less 



subulate. Malva ; Campanula. 

 (]3) Unicellular subulate ; surface rugose, with papillae. Cuphea ; 



Nerium; Eutoca. 

 (y) Unicellular, but flattened, or spathulate, rugose or striate. 



Yerbascum ; Oelsia ; Antirrhinum. 

 (§) Pluricellular ; simple ; smooth. Salvia (some forms) ; Ad- 



hatoda. 

 (e) Pluricellular; simple, rugose, or striate, not glandular. 



Anagallis; Groldfussia; Thunbergia. 

 (^) Pluricellular ; branched, not glandular. Browallia ; Salvia 



(some forms). 

 (»)) Pluricellular, with glandular tip. Oxalis ; ^sehynanthus ; 



Gesnera. 

 (0) Multicellular. Convolvulus ; Ipomsea ; Lasiandra. 



Stamen hairs have been observed by the writer in the follow- 

 ing nineteen natural orders, viz. : — Malvaceae, Oxalidacese, Melas- 

 tomacese, Eutacese, Hydrophyllacese, Lythracese, Campanulacese, 

 Lobeliacese, Convolvulacese, Rubiacese, Apocynacese, Labiatse, 

 Acanthacese, Scrophulariacese, Gesneracese, Ericaceae, Primulacese, 

 Commelynacese, Liliacese ; ^ but it is probable that further investi- 

 gation will reveal their presence in very many others. 



^ Since tlie foregoing was written, hairs have been observed on the stamens of Crocus, 

 thus adding to the above list the IridacBte. 



