XVI PROCEEDINGS OF THE 



fore appears to have arrived when a list, complete to the present 

 time, of the known spiders of Great Britain and Ireland under 

 the names to which, according to the laws of priority, they appear 

 to be entitled, seems to be a desideratum. Dr. Thorell, indeed 

 (Syn. Eur. Spid. p. 471), gives a list of British spiders ; but it is 

 complete only to the date of Mr. Blackwall's work, ' Spiders of 

 Grreat Britain and Ireland,' since the publication of which the 

 number of known indigenous species has increased by nearly one 

 half. The systematic arrangement of Mr. Blackwall has not been 

 adopted in this list, appearing, as it did, to be too artificial and 

 based on insufficient (though in some respects convenient) cha- 

 racters, and, moreover, never to have found favour with other ara- 

 neologists. The present arrangement (though it has no preten- 

 sions to finality) is the result of a long and tolerably careful study 

 of spiders from many and widely distant regions of the world. It 

 begins at the opposite end to that where Dr. Thorell and Dr. 

 Koch begin their systematic arrangements ; but it is, in the 

 main, not very discordant with that of the former of these 

 authors, as put forth in his valuable work * On the G-enera of Eu- 

 ropean Spiders,' a work to which the writer is indebted for many 

 most valuable hints on the classification of the Araneidea. 



2. " Some observations on the Vegetable Productions and Eural 

 Economy of the Province of Baghdad." By William Henry 

 Colvill, Surgeon-Major H.M. Indian Eorces, Civil Service, Baghdad. 

 Communicated by Dr. Hooker. 



3. " Note on the Bracts of Crucifers." By M. T. Masters, 

 Esq., M.D., E.R.S. 



The subject was divided by the writer into two branches : — 1. The 

 absence of bracts in Crucifers. In the majority of cases this is 

 so complete that even in the earliest stages of development ob- 

 served by Payer no trace of bracts is seen. Different explanations 

 of the phenomenon have been given by different morphologists. 

 A. P. De CandoUe attributes it to congenital suppression of the 

 parts ; Godron to pressure acting from within outwards, result- 

 ing from the dense manner in which the young flowers are packed 

 together ; Norman and Eichler consider that the bracts are abor- 

 tive, but potentially present, the latter writer combating Godron's 

 view by the consideration that on the one hand the bracts are 



