76 Retrospective Criticism. 



phyllum speciosa, but as it is a more viojorous grower, it should be 

 more sparingly watered in winter. Speciosissimus flowers with us 

 abundantly every season; we give it plenty of water, as we do all 

 the cactuses, from April to August, and keep it cool and dry from 

 August to April, pinching off the tips of the most thrifty stems, to 

 make them form stronger buds. 



Echinocactus Eyriesu is exceedingly beautiful: it has a spherical 

 head, six or eight inches in diameter, from the ribs of which spring 

 the flowers, which are nine inches long, pure white, hiohly fragrant, 

 opening at night, and, in our opinion, it is one of the finest of the 

 tribe. It flowers two or three times a year, and is treated like the 

 cereuses. 



Cereus triangularis is white, with a larger flower than C. graudi- 

 flora. 



The work of the Abbe Berlese, on the Camellia, is pul)lished semi- 

 monthl}', with two plates each, price about sixty cents each part, 

 delivered in Boston. The text is printed in French. Sixteen num- 

 bers are now issued, containing thirty-two plates. It may be had by 

 applying to us. 



Mrs. Loudon, (not the Misses Loudon,) is publishing a work on 

 bulbous rooted plants, with plates, quarto size, four plates in each 

 number; price about seventy-five cents per number. It is a beauti- 

 ful work, and well worth possessing by every lover of bulbs, par- 

 ticularly those from the Cape of Good Hope. It is now published as 

 far as the sixth number, and will be completed in twelve or fourteen 

 numbers. 



We believe we have answered the queries of Mrs. H, M. B., and 

 at somewhat greater lengch than is our custom; we shall, however, 

 always be willing to oblige our readers in this respect, when we have 

 the leisure to do so. For any more than what we have now noted 

 down, we must refer all who wish for information on the above plants, 

 to the articles in our previous volumes. — Ed.] 



Hot loater apparatus for heating green-houses, 4'C. (Vol. VI., p. 

 70. — I was much pleased with the description of an apparatus for 

 heating plant-houses with hot water, by your correspondent, H., of 

 Columbus, Ohio, in the February number of the Magazine. The 

 plan appears more economical and simple than any heretofore notic- 

 ed. A more minute description of the apparatus, no doubt, would be 

 acceptable to many of your readers, besides myself. Could you not 

 induce your correspondent to communicate the information desired.'' 

 whether his boiler is cast iron or cojiper, and what metil the pipes .'' 

 Whether it is necessary to have the boiler and reservoir, one or both, 

 air tight.^ the probable quantity of fuel, say coal, it will require in 

 a season, to keej) it in operation, provided the^green-house is detach- 

 ed from the mansion, and the whole of the heat applied to heating 

 the plant structure.^ and, above all, the cost of such an apparatus, 

 including boiler, reservoir, and pipes.^ I intend, next season, to erect 

 some kind of an additional heating apparatus, and, for that reason, 

 would be thankful for any information on the subject. — J. B. Gar- 

 ter, Columbia, Pa., Jan. 25, 1841. 



[Our correspondent, H., will, no doubt, comply with the wishes of 

 Mr. Garber, should this meet his eye. — Ed.] 



