250 Transactio7is of the ' [Sess. 



Fragilaria capucina. Diatoma elongatum. 



Eunotia arcus. ' n n var. ;8. 



Synedra splendens. i 11 vulgare. 



It ulna. Nitzschia linearis 



Tabellaria flocculosa. 

 Licmophora fiabellata (marine). 

 Grammatophora marina (marine). 

 Denticiila ocellata. 



II tenuis. 



sigmoidese. 

 C. Cryptoeaphidie^. 



Isthmia nervosa (marine). 

 Cyclotella operculata. 



X.—NOTE ON THE GENUS LAMIUM. ' 

 By Mr MARK KING. 

 [Read Feb. 26, 1885.) 



The Natural Order of the Labiatae, in which the genus Lamivjn is 

 found, is one of the best marked and most easily recognised of all 

 the botanical groups. The Labiates are confined to the temperate 

 regions of the earth, their number diminishing towards the tropics 

 and either pole. The Lamiums, or Dead-nettles, are perhaps the 

 best-known plants of the Order, — indeed they are so familiar to all, 

 that they are frequently passed by with, it may be, a single glance ; 

 and yet, like many of their humble neighbours, they possess a most 

 interesting structure, and well repay any labour which may be 

 spent in their study, as is evidenced by the remarks upon the 

 common Dead-nettle in Sir John Lubbock's most readable book on 

 the ' Fertilisation of Wild Flowers.' Although mainly following 

 Hooker, in his last edition of the ' Student's Flora of the British 

 Islands' — (the latest and best arrangement of our native plants) — 

 I may state that I have given some attention to the genus Lam.ium, 

 and would desire to add my own remarks from observation of the 

 living plant from time to time. Perhaps the most striking family 

 resemblance in the Lamiums is found in the whorled inflorescence, 

 ■with the leafy bracts, these latter being often three or four times 

 as large as the leaves. The generic name is probably derived from 

 the Greek word for a throat, in allusion to another well-marked 

 characteristic — namely, the throat-like corolla. There are at 

 least Jive species of Lamium indigenous to, or thoroughly estab- 

 lished in, this country, and of these four may be considered as 

 generally distributed over Britain. The genus is conveniently 

 divided into annual and perennial plants, — the annual forms being 

 Lamium purpureum, L. intermedium, and L. amplexicaule ; while 



