478 Letters, Extracts, Notices, &;c. 



transverse rows round the limb and in longitudinal rows on 

 the digits. Where the two sets of scales meet interference 

 occurred and led to modifications. He showed further how 

 such interference might lead, in the case of a pentadactyle 

 wing, to the occurrence of a gap after five secondary quills, 

 and extended his argument to Aves generally, suggesting 

 that " diastataxy " was " architaxy," and that " eutaxy " 

 was a secondary modification that might easily have oc- 

 curred at different times in different groups. 



On the same evening Mr. W. P. Py craft, A.L.S., read 

 a paper entitled " Some Facts concerning the so-called 

 ' Aquintocubitalism ' in the Bird's Wing.^' He showed, by 

 means of a series of lantern-slides, that ^* aquintocubitalism " 

 was due to a shifting, backward and outward, of the 

 secondary remiges 1-4 and of the horizontal rows of coverts 

 1-5. The result of this shifting was to dissociate all the 

 coverts preaxial to the 5th remex, i. e. all the coverts col- 

 lectively forming one obliquely transverse row in front of 

 the remex : the 5th remex forming a new connection with 

 the corresponding row immediately behind — the 6th ; while 

 the 6th remex formed a fresh union with the 7th row, and 

 so on. Tlius the 5th remex was shown to have lost its 

 original relations with its covert, and not its existence as 

 was supposed. The teims — suggested by Prof. E. Ray 

 Lankester — " stichoptilous " and " apoptilous " were pro- 

 posed as substitutes for the older and less convenient terms 

 quinto- and aquintocubitalism. All wings, it was shown, 

 are, in the embryo, stichoptilic, and later may become 

 apoptilic. Hence the author felt inclined to regard the 

 former as the more primitive arrangement. 



Avimn Genermn Index Alphabeticus. — We wish to call 

 the attention of all our friends engaged in ornithological 

 work to the alphabetical index of the generic names used in 

 the British Museum Catalogue of Birds which has been just 

 issued as the ninth volume of the ' Bulletin ' of the B.O.C. 

 under the title given above. Mr. Waterhouse^s careful com- 

 pilation will, we are sure, be much appreciated by all who 



