PROCEEDINGS OP THE SOCIETY. 359 



Area — a work which owed its existence very largely to the 

 members of the Natural History and Geological Societies of 

 Glasgow; (2) Archceology, Education, Medical, and Charitable 

 Institutions of Glasgoiv ; and (3) Local Industries of Glasgow 

 and the West of Scotland. 



On behalf of Mr. Robert S. Houston, there was exhibited the 

 Creeping Water Cress, Nasturtium sylvestre, R.Br., gathered in 

 some abundance by Mr. Robert Smith near Johnstone, Renfrew- 

 shire. This is a rare species, doubtfully indigenous in Scotland. 

 Mr. Alex. Somerville, B.Sc, F.L.S., who had brought forward 

 Mr. Smith's specimens, for the sake of comparison, exhibited 

 examples of the plant from his own herbarimn, as well as 

 Nasturtium palustre, DC, and N. amphibium, R.Br., (a) 

 indivisum, DC, and (b) variifolium, DC, from various Scottish 

 and Irish localities. Mr. Lawrence Watt also exhibited a very 

 fine specimen of N. sylvestre, gathered on waste ground near a 

 paper mill in Dumbartonshire 



Mr. Jolm Lindsay, M.A., M.B., CM., exhibited some specimens 

 of Double-headed Monsters, and by diagrams and blackboard 

 sketches explained his theory of the causes which led to so 

 many curious phenomena. Dr. Gemmill afterwards rather 

 adversely criticised the positions which the tlieory advanced. 



Mr. George Russell exhibited a beautiful specimen of Rhipi- 

 dojiteris peltata, Schott., a mountain fern from Mexico showing 

 a large number of fertile fronds. It differs from the rest of 

 the Acrostichece in having the sporangia on the upper side of 

 the fronds. 



Mr. Russell also showed a New Zealand caterpillar, a species 

 of Hepialus, belonging to the same genus as the British Ghostr 

 moth {Hepialus humuli, L.). The New Zealand species is 

 attacked by a fungus, Cordiceps robertsii. The spores enter 

 the caterpillar while alive, but the animal is gradually killed 

 by the fungus living and growing upon its tissue. After a time 

 the caterpillar is completely dried up and hardened, and there- 

 after a " stroma " grows up, on which fresh spores are pro- 

 duced, ready to enter any other Hepialus which may come in 

 contact with them. 



Mr. George Cleland reported on the Society's excursion to 

 Arniston and Temple on 2.3rd September (see page 334), and 



