A Catalogue of the Fifty Plants from Chelsea Garden, Presented to the Royal Society, by the Worshipful Company of Apothecaries, for the Year 1754, Pursuant to the Direction of Sir Hans Sloane, Baronet, Med. Reg. & Soc. Reg. Nuper Praeses, by John Wilmer, M. D. Societat. Pharmaceut. Lond. Socius, Hort. Chels. Praefectus & Praelector Botan

XVIII. A Catalogue of the Fifty Plants from Chelsea Garden, presented to the Royal Society, by the worshipful Company of Apothecaries, for the Year 1754, pursuant to the Direction of Sir Hans Sloane, Baronet, Med. Reg. & Soc. Reg. nuper Praeses, by John Wilmer, M. D. Societat. Pharmaceut. Lond. Socius, Hort. Chelf. Praefectus & Praelector Botan. Read April 10, 1601 1755. Antirrhinum Siculum Linariæ folio, niveo flore, Tilli. 1602 Calcalia caule herbaceo foliis hastato-sagittatis denticulatis, petiolis superne dilatatis. Hort. Upsal. 254. 1603 Calamintha Hispanica frutescens Mari folio. Inst. R. H. 194. Melissa fruticosa ramis attenuatis virgatis foliis subtus tomentosis. Linn. Sp. Plant. 593. 1604 Calendula foliis obverse ovatis denticulatis, caule fruticoso perenni. Fl. Leyd. Prod. 531. 1605 Campanula hortensis rapunculi radice repente. M. H. 2. 460. Campanula repens flore minore cæruleo. J. B. 2. 706. 1606 Caryophyllus minimus muralis. C. B. 211. Lychnis minima muralis. M. H. 2. 547. 1607 Cephalanthus foliis oppositis ternisque. Fl. Virg. 15. Scabiosa Scabiosa dendroides Americana ternis foliis caulem ambientibus, floribus ochro-leucis. Pluk. Alm. 336. 1608 Cerinthe quorundam major, fl. ex rubro-purpurascente. J. B. 3. 603. 1609 Chenopodium Lini folio villoso. T. 506. Linaria scoparia. C. B. P. 212. 1610 Clematis Hispanica surrecta altera et humilior, fl. albicante. H. R. Par. 1611 Clymenum Hispanicum flore vario, siliqua articulata. T. 396. Lathyrus vicioides vexillo rubro, petalis rostrum ambientibus caeruleis. M. H. 2. 50. 1612 Cochlearia altissima Glasti folio. T. 215. Lepidium. C. B. 96. 1613 Conyza latifolia viscosa suaveolens flore aureo, ex Gallo-provincia. Tourn. 455. Conyza Pyrenaica foliis Primulae veris. Par. Bat. 127. 1614 Coreopsis foliis linearibus integerrimis caule erecto. Fl. Virg. 18. 1615 Corispermum Hyssopifolium. D. Jussieu, Ac. Reg. Sc. 1712. 1616 Digitalis Hispanica purpurea minor. T. 165. Digitalis Verbasci folio purpurea minor perennis Hispanica. Bar. Icon. 1183. 1617 Diplocus folio laciniato. C. B. P. 385. 1618 Dodartia foliis lanceolatis ferratis, floribus spicatis. Linaria Bellidis folio. C. B. P. 212. Prod. 106. 1619 Fabago triphylla et tetraphylla flore tetrapetalo, fructu membranaceo quadrangulari. Burm. pl. Afric. 7. Tab. 3. Zigophyllum capsularum angulis compresso membranaceis. Linn. Sp. Plant. 383. 1620 Geranium Anemones folio. Par. Bat. 178. 1621 Heliotropium Canariense arborescens, fol. Scorodoniae. H. Am. 129. 1622 Hermannia fol. Ibisci hirsuto, flore primo luteo, deinde purpuro-rubello. An Hermannia frutescens folio oblongo molli cordato hirsuto. Boerh. Ind. Alt. 1623 Hesperis lutea siliquis strictissimis. Tourn. 222. Draba lutea quibusdam. J. B. 2. 870. 1624 Hieracium Echioides capitulis Cardui benedicti majus Arabicum folio sinuato. Hort. Edinburg. 1625 Hieracium Pyrenaicum longifolium amplexicaule. T. 472. 1626 Jasminoides aculeatum humile Halimi minoris folio, flore majore violaceo, fructu crassiore per maturitatem flavescente. Michel. Nov. Gen. 224. 1627 Ketmia Ægyptiaca Vitis folio, parvo flore. Tourn. 1628 Lathyrus Tingitanus siliquis Orobi, fl. amplo ruberrimo. M. H. 2. 55. 1629 Lotus leguminibus conjugatis membranaceo quadrangulis bracteis oblongo-ovatis. Linn. Sp. Plant. 774. Lotus luteus siliqua angulosa. Boer. Ind. Alt. 2. p. 37. 1630 Lychnis segetum rubra foliis Perfoliatæ. C. B. 204. Vaccaria. Dod. Pempt. 104. 1631 Marrubium Hispanicum calyce stellato et aculeato. I. R. H. 182. Alysson Galeni. Clus. Hist. 35. 1632 Medica major erectior, floribus purpurascenti- bus. Tourn. 410. 1633 Mespilus foliis ovatis serratis, pomis ovatis ex luteo virentibus nobis. 1634 Mespilus foliis ovatis, obtusis, crenatis, spinis longis tenuibus, fructu singulari rotundo, umbilico foliaceo. An Mespilus Virginiana. Uvae crispa foliis. Pluk. Mant. 1635 Ornithogalum humile foliis ovatis sessilibus, floribus corymbosis, nobis. 1636 Osteospermum foliis oblongis acute dentatis, caule fruticoso diffuso, nobis. 1637 Othonna foliis pinnatifidis laciniis linearibus parallelis. H. Cliff. 419. Jacobea Africana frutescens foliis Absinthii umbelliferi incanis. H. Amst. 2. p. 137. 1638 Pelecinus vulgaris. T. 417. Astragalus purpu- reus annuus peregrinus, siliquis utriusque serrae similibus. M. Hist. 2. 107. 1639 Phyllis stipulis dentatis. Flor. Leyd. Prod. 92. Valerianella Canariensis frutescens simpia nobla dicta. Hort. Eltham 405. 1640 Plantago angustifolia paniculis Lagopi. C. B. 374. 1641 Ruyischiana floribus verticillatis, nobis. 1642 Samolus Valerandi. J. B. 3. 791. Anagallis aquatica folio rotundo non crenato. C. B. P. 252. 1643 Scabiosa stellata folio laciniato major. Tourn. 1644 Solanum spiniferum frutescens spinis igneis Americanum. Pluk. Phyt. 225. fig. 5. 1645 Telephium Dioscoridis Imperati. Telephium repens folio non deciduo. C. B. P. 287. 1646 Thalictrum minus alterum Parisiensium foliis crassioribus et lucidis. H. R. Par. 1647 Tithymalus maritimus. C. B. P. 291. Tithimalus paralius. J. B. 3. 674. 1648 Trifolium Bitumen redolens. C. B. 327. 1649 Trifolium Bitumen redolens angustifolium. Boer. Ind. Alt. 2. p. 32. Trifolium bituminosum arboreum angustifolium ac sempervirens. Hort. Cath. 1650 Virga aurea Canadensis foliis carnosis non serratis latioribus. Hist. Oxon. XIX. A Letter to the Right Honourable George Earl of Macclesfield, President of the Royal Society, on the Advantage of taking the Mean of a Number of Observations, in practical Astronomy: By T. Simpson, F. R. S. My Lord, Read April 10, 1755. It is well known to your Lordship, that the method practised by astronomers, in order to diminish the errors arising from the imperfections of instruments, and of the organs of sense, by taking the Mean of several observations, has not been so generally received, but that some persons, of considerable note, have been of opinion, and even publicly maintained, that one single observation, taken