530 EOBINSON. 



Nicolson referred is clearly shown by the expression "sub Jalapiae 

 nomine." Of this plant Plukenet gives a figure cited by Ray and 

 doubtless in the opinion of Ray representing his plant. This figure 

 shows a highly conventionalized twiner with alternate deltoid-ovate 

 entire leaves and solitary short-peduncled axillary flowers. The flow- 

 ers show no corolla but merely ^a smallcalyx with relatively short lobes 

 which do not equal the tube. It is impossible to regard this figure 

 as representing /. cathartico, Poir. which is characterized by calyx- 

 lobes of unusual length, greatly exceeding the short tube. The 

 writer after some search has failed to find that Linnaeus expressed 

 any opinion in regard to the identity of this particular figure of 

 Plukenet, and from its general lack of detail it would probably be 

 impossible to place it with any certainty. 



It may be seen from the data here assembled 1) that Nicolson made 

 no Convolvulus africanus, a name which seems to have arisen from a 

 clerical error of Choisy. 2) that Nicolson in employing the name 

 Convolvulus americanus had no thought of coining a new designation 

 or describing a new species, but was merely applying — in all proba- 

 bility erroneously — the pre-Linnaean Convolvulus Americanus of 

 Ray to a purgative twiner of Santo Domingo. He gives no botanical 

 characterization sufficient to give validity to the name and merely 

 discusses briefly the pharmaceutical properties. Nicolson's type is 

 not known and even if the plant he was treating could be ascertained 

 it is doubtful if the botanical type of Convolvulus americanus would 

 not have to be sought in the plant of Ray, whose name Nicolson was 

 intending to apply, rather than the plant to which he perhaps mis- 

 takenly applied it. As we have seen, the plant of Ray may be traced 

 back to a figure of Plukenet's which cannot be I. cathartica Poir., 

 a well known name that thus relieved of an earlier synonym retains 

 its validity. 



Ipomoea crassicaulis (Benth.), comb. nov. Batatas ? crassi- 

 caulis Benth. Voy. Sulph. 134 (1844). Ipomoea fistulosa Mart, ex 

 Choisy in DC. Prod. ix. 349 (1845). /. tcxana Coult. Contrib. U. S. 

 Nat. Herb. i. 45 (1890). 



Operculina ornithopoda (Robinson) House, var. megacarpa 

 (Brandegee), comb. nov. Ipomoea sp. Rose, Contrib. U. S. Nat. 

 Herb. i. 344 (1895). /. megacarpa Brandegee, Zoe, v. 218 (1905). 

 Operculina Roseana House, Bull. Torr. Bot. Club, xxxiii. 500 (1906) ; 

 Bot. Gaz. xliii. 414 (1907). Formae typicae floribus fructu etc. simil- 

 lima differt foliorum segmentis multo latioribus(0.9-3.5 cm. latitudine). 

 The writer agrees with Mr. House that this plant, differing in range 



