REVIEWS OF NEW PUBLICATIONS. 57 



been concealed in some of the chemical substances employed in Mr. Crosse's 

 researches, and have been hatched by the galvanic influence of the battery. The 

 point can, however, hardly be said to be settled, and we should be glad to receive 

 further observations on a subject so interesting. 



Our readers will recognize in Mr. Murray an early contributor to The 

 Naturalist.— The pamphlet is dedicated " to George Fife Angas, Esquire." 



A Descriptive Account of the Palo-de-Vaca, or Cow-tree of the Caracas. 

 With a Chemical Analysis of the Milk and Bark. By John Murray, F.S.A., 

 F.L.S., &c. London: Effingham Wilson, Royal Exchange. 1837. Royal 8vo. 

 pp. 24. 



A considerable portion of the matter contained in these pages was commu- 

 nicated by Sir R. K. Porter, the chemical analysis only being by the author. 

 We have been much interested in their perusal ; and are alone deterred from 

 giving a summary of their contents by an unwillingness to detract from their 

 circulation. An engraving of this wonderful milk-yielding tree is supplied at 

 the beginning of the pamphlet, which is inscribed, " with great propriety," we 

 are informed, to Sir Robert Ker Porter. — In England we are content to obtain 

 the " staff of life " from Wheat — or even from Rye, Barley, &c. — and milk from 

 Cows, Goats, Asses, &c, but we here learn that a good mess of bread and milk 

 may be procured in the Caracas from the bountiful Palo-de-Vaca, or Cow-tree — 

 credat Judceus ! But for further and ample particulars we refer our readers to 

 Mr. Murray and Sir. R. Porter. 



A History of British Birds. By William Yarrell, F.L.S., Sec. Z.S. U- 



istrated by a Wood-cut of each Species, and numerous Vignettes. London : 



John Van Voorst, 1, Paternoster Row. Nov. 1837. Part iii. 



The illustrations of birds in this third number scarcely satisfy our expectations, 



lough some few almost equal any in preceding parts for spirit and truth. We 



trust this falling-off is only temporary, and that subsequent publications will not 



tend to justify the doubtless erroneous suspicion — which has already reached our 



irs — that so much pains were taken with the wood-cuts in the first part merely 



to ensure a large sale for the work. 



The letter-press maintains the admirable character which we have previously 



lad occasion to commend ; and in this department at least we think we have an 



ample guarantee, in the name and acquirements of the amiable author, that 



nothing of an inferior nature will be admitted. The work is published in alter- 



vol. in. — no. XVI. I 



