162 



THE NATURALIST. 



Eednecked Grebe, Podiceps ruhricollis. One was found dead upon the 

 shore at Hammer in Tebruary, 1861. 



Gannet, Sula hassana, Altliougli a few sometimes remain during tlie 

 winter, tlie appearance of this bird is so uncertain that it can only be 

 considered an occasional visitor. 



Wedgetailed Gull, Larus Rossii. In the summer of 1854, I shot a 

 gull, wbicb, although, unknown to me at the time, and unfortunately lost, was 

 without doubt an example of this rare species. Its description and measure- 

 ment are still in the note book which I carried at the time. 



Sabine's Gull, L. Sahini. Two examples have occurred to my know- 

 ledge. 



SUMMAEY OF THE BIEDS OF SHETLAND. 





6 



9 



1 



5 



12 



= 33 



Migrant Natives .... ...... 



.......... 0 



2 



0 



4 



11 



- 17 





2 



7 



0 



9 



19 



= 37 





1 



4 



0 



1 



3 



9 





12 



36 



3 



16 



11 



= 78 





21 



58 



4 



35 



56 



= 174 



Baltasound, Shetland, August 2nd, 1865. 



NOTES ON THE COMMON GAEDEN SNAIL. 

 (Helix aspersa.) 



By Thomas Graham Ponton. 



However common an animal may be, I believe that there are generally 

 some minute particulars in its habits and economy which will be found to 

 repay investigation. 



It was this belief which induced me to breed and keep in captivity a 

 common garden snail, and to make some investigations into its habits, the 

 results of v/hich are now laid before the reader — None of the facts given are 

 probably altogether new, but some of them may perhaps be unknown, and 

 prove of interest to the readers of the Naturalist 



