130 First and last Appearances of 



form different distinct beds, in which will be found remains 

 of fresh-water fish, of vegetables, and of quadrupeds. Large 

 animals are frequently borne along by the rapidity of the cur- 

 rent, and precipitated down the cataracts : their broken bones, 

 mixed with the calcareous sediment, may form rocks of cal- 

 careous tufa, where the waters first subside after their de- 

 scent.'* 



It may be proper to remark, that the partial drainage of 

 Lake Erie will also effect a corresponding drainage of the 

 other lakes connected with it, and add many thousand square 

 miles of productive soil to the continent of North America. * 



Art. IV. Dates of the first and last Appearances of the Hirun" 

 dines in the Neighbourhood of Allesley Rectory, for the Year 1829, 

 with Remarks, By the Rev. W. T. Bree, M. A. 



Sir, 



Your correspondent, L. E. O. of Bradford (Vol. II. p. 458.), 

 communicates the interesting fact of his having observed the 

 common swallows (he does not state the number of them), on 

 the 15th of November, at Richmond in Yorkshire. This is 

 certainly late in the season for these birds to be seen; later, 

 indeed, than I have ever observed them, except in one in- 

 stance, which was on November 20th, as appears by referring 

 to the table of arrivals and departures (Vol. II. p. 19.) under 

 the year 1806 ; and in this instance it was only a single bird 

 that was seen. 



Your correspondent is pleased to say that " it was his in- 

 tention to have communicated this previously to the present 

 time, in the form of an essay on the arrival and departure of 

 the jHTirundines, along with some other observations and facts 



* The few rock specimens my son brought from the vicinity of Niagara 

 are: — 



1. A hard subcrystalline grey limestone. 



2. A dark very close-grained limestone. Both the specimens closely 

 resemble some of the lower beds of English mountain or transition lime- 

 stone. 



3. The same dark limestone, with an indistinct vestige of chain coral, in 

 which the organic part is chert. In this specimen there is a small string of 

 yellow blende (sulphuret of zinc). The above three specimens are from 

 the hard limestone (dd) in fig. 23. 



4. A dark argillaceous limestone, from the shale h h. 



Though there are few organic remains in the limestone at the Falls, the 

 mineral characters indicate that it belongs to the transition class of rocks. 

 — n, i?., Seiu 



