^56 Notes. [vJ.-^xx^Mii: 



Slugs and Snails. — Owing to the unprecedented iiuml)er of 

 rainy days during the last two or three months, slugs and 

 snails (introduced) have ravaged suburban gardens as never 

 l)efore. Acting on Prof. Ewart's advice in the Journal of 

 Agriculture to deprive the slimy pests of their favourite foods, 

 I refrained from i)lanting the dainties they usually prefer, 

 with the result that geraniums, roses, broad iieans. ferns, and 

 even wattle trees were attacked. Some specimens of Acacia 

 decurrens. var. mollis, were almost defoliated, the slugs 

 ascending to a height of 15 to 20 feet. Incidentally, two items 

 which may be of interest to nature students came under my 

 notice. Firstly, while by sunrise all slugs and snails which 

 had been feeding on lowlj- herbage were under cover, it was 

 the nde, without exception, to see on the wattle trees slugs — 

 rarely snails — homing as late as 8.30 a.m. — at least two hours 

 after suniise ; these kept to the shady side of the tree-trunks. 

 Near the base I had placed a ])and of rope soaked in phenyle. 

 Here the pests accumulated, making vain exclusions up and 

 round the trunks to hnd a way home, but in vain, and were 

 destroyed. Secondly, each morning during the past week 

 slugs were to be seen susjjended by threads of slime from the 

 lower branches of one of the wattle trees. Some of these 

 threads were four or five feet long, antl lengthened, a;> though 

 " paid out," as we watched, the slugs hanging always -head 

 downwards, fully extended, with tentacles protruded, and 

 gyrating slightly when swayed by the light breeze. No slug 

 was seen to reach the ground in this way, for either the 

 suspending filament of slime snapped or was deliberately cut 

 off by the animal when from six to nine inches from the ground. 

 The slugs fell heavily, and after a few seconds hastened away 

 to cover as rapidly as possible. This action on the part of 

 slugs is, in my experience, unique, and it would be interesting 

 to know if noticed elsewhere. It would seem that they had 

 miscalculated the time necessary for the homeward journey, 

 and, instinctively avoiding those branches on which the sun 

 was shining, ado})ted this method of descent to their retreat 

 in the base of a roj)rosma hedge. Whether the suspensory 

 filament failed through txposure to a fast drying atmos])here, 

 or,' becoming brittle, snapped on account of the tension, or 

 whether the animal was abli- to stop the extrusion of the 

 filament in order to hasten its retreat from increasing light and 

 aridity, are questions I am unable to satisfactorily answer. — 

 A. D. H.\RDY. Kew, qth December. igi6. 



