ON THE POSSIBILITY OF TAKING A ZOOLOGICAL CENSUS. 23 



bauds ; legs testaceous ; wings cinereous ; with a brownish tinge along 

 the costa ; discal transverse vein straight, parted by one fourth of its 

 length from the border and by about its length from the oblique prse- 

 brachial transverse vein; halteres testaceous. Length of the body 6 

 lines ; of the wings 9 lines. 



Gen. Sophira, Walk. 



14. Sophira bipars, n. s. Fcem. Fulva, nitens, abdomine nigro basi 

 fulvo, alis nigris margine postico cinereo limpido-mterlineato. 



Female. Tawny, shining, with a few black bristles ; head and pectus 

 paler ; 3rd joint of the antennae linear, rounded at the tip, not reach- 

 ing the epistoma ; arista simple ; abdomen oval, black except towards 

 the base, shorter than the thorax ; wings black, w ith a cinereous partly 

 limpid stripe on the hind border ; this stripe is interrupted by a black 

 streak which extends along the discal transverse line ; a pale point on 

 the middle of the costa; discal transverse vein straight, parted by 

 half its length from the border, and by about its length from the 

 prsebrachial transverse, which is rather long. Length of the body 2\ 

 lines; of the wings 7 lines. 



On the Possibility of taking a Zoological Census. 

 By Aleeed Newton, M.A., F.L.S. 

 [Read March 21, 1861.] 



It is now nearly five years since my friend, the late Mr. John 

 AVolley, to whose genius as a naturalist I am proud to own my many- 

 great obligations, suggested to me in a letter the possibility of 

 taking a census of the birds of these islands. The period of 

 numbering the human population of the British Empire, which is 

 now so close at hand, makes me think the present time, when 

 men's minds are turned to the subject, not inopportune to bring 

 to the notice of this Society the advantages which might possibly 

 accrue to Zoology by taking an approximate census, not only of 

 our birds, but also of the other divisions of our fauna. I believe 

 that naturalists will bear me out in the assertion that hitherto 

 nothing of this kind has ever been attempted in any branch of the 

 science, and also that (with perhaps very few, but highly laudable, 

 exceptions) no writer has ventured to express in any convenient 

 form the relative proportion which the number of individuals of 

 one species bears to those of another. In almost all local faunas 

 the abundance or scarcity of different species is expressed in very 

 arbitrary, not to say vague, terms. We find nothing more definite 

 than the words '•'common," "frequently met with," "rare" or 

 <! occasionally seen" appended to the names of animals in some 



