Rock Birds of Britain, 573 



for fine injections, or with thick flour-paste, or even [paste of] 

 pounded chalk, and inject gently till every part is plump and 

 well extended. Let the specimen hang up to dry for a few 

 hours till the injection is firm ; then clean the aperture with a 

 penknife, and extend the legs as you would those of insects. 

 I have minute spiders as well as the giant ^ranea «vicularia 

 L, [ikfygale avicularia W.'] ; dull-coloured kinds, as well 

 as those clad in robes of gold and silver [see in p. 570.]j 

 so well preserved, that they could not be told from living 

 specimens ; and all is done in less time than is taken to describe 

 the process. In my case of preserving instruments, I have 

 coloured powders to tinge the injections : but they are seldom 

 used. A small portion of corrosive sublimate or arsenic 

 mixed with it would expel mites, but this would not be ne- 

 cessary in well-kept camphorated cabinets. 

 St, Vincent, May 1. 1830. 



\_0n preserving the Shells of Eggs for Cabinets, see, besides 

 the advice above by Mr. Guilding, that of Mr. Waterton in 



V. 515.: see, also, in IV. 145., An Observer of Nature's 

 figure and description of an instrument (similar in principle 

 to that of Mr. Guilding) which he had had made for with- 

 drawing from egg-shells their contents : see in VI. 171., Mr. 

 Murray's suggestion of the employment of the air-pump for 

 this purpose : see in I. 492. 



On the Preservation of the Colours of the Fleshy Bodies of 

 certain Insects, see Mr. W^aterton in VI. 90. On the pre- 

 servation of dead insects generally, see V. 495. 683.746.; 



VI. 90, 91. 554, 555.'] 



Art. V. The Accumulation of all possible Information respecting 

 the Habits of the Rock Birds of Britain, by the cooperative 

 Agency of Naturalists residing near Headlands on the Coasts, 

 suggested. By J. D. Salmon, Esq. 



In the notices with which naturalists have favoured us of 

 the arrival in, and departure from, Britain of the birds of 

 passage, they have confined themselves, for the most part, to 

 the species which visit, for the purpose of incubation, during 

 summer, the interior of the country ; while scarcely any 

 information has been published on the migratory movements 

 of the equally numerous species of rock birds ; although some 

 of these, like a greater part of the others, leave, on the 

 approach of autumn, their place of nidification, to migrate to 

 other countries, from north to south, or vice versa. 



I wish to draw the attention of those who reside nearest 



