294 



<2300 m.). (1) A barren braucli with long (Opines ami leaves vary- 

 ing from obovate-cuneate to elliptic-oblong, and, on tlie sliort- 

 shoots, to lanceolate-oblorig, deutate-crenate or serrate, fairly hairy 

 below and provided with narrow foliaceous stipules; branches 

 with very similar foliage occur occasionally on the Kew tree: 

 <|3)a fruiting branch with small leaves, mostly elliptic oblong and 

 often quite obtuse, 2 4-5 cm. by 1-2-2-2 cm., of even smaller; the 

 leaves resemble those of the barren branch of the Paris specimen 



described above, but they are more obtuse. 



2. Coulter,"" no. 84, Eeal del Monte.- This locality is 



situated very close to Morau, the locus classicus of C. imhescens. 

 The leaves are elliptic to elliptic-oblong, obtuse, very minutely 

 creuate-deutate and accompanied by broad foliaceous stipules. 

 Tlie specimen is in flower. Similar leaves occur very rarely in 



the cultivated f . sliimlacpa. 



Puebla. o. Liebmann, Guinnntla (2100 m.). A fruiting branch, 



intermediate between Coulter, no. 84, and i.HumhoIdtU. 



Vera Cruz. 4. Galeotti, Jalapa. A flowering branch; leaves 

 lanceolate-oblong, subacute, distinctly and unequally crenate in 

 ihe upper part, 4^5 cm. long, 1-5-1-8 cm. wide, glabresccnt. 



5. Linden, no. G56, April, 1838, la Iloya los 

 Yigas. A small flowering branch, very like Galeotti's. 



6. C. G. Pringle, no. 8081, thickets about Jala]3a 

 (1300 ni.), March, 1899. Two flowering branches and a young long- 

 shoot with obtusely three-lobed leaves. The corymbs terminate 

 either short-shoots with very narrow early deciduous stipules or 

 long-shoots with foliaceous and more persistent stipules. The 

 range of variation in the shape of the leaves of the flowering pieces 

 is very great, being from obovate to elliptic and lanceolate. The 

 leaves are mostly obtuse, their crenation or denticulation is dis- 

 iiuct, with traces of lobing, and their tomentum is scanty. They 

 measure 3 5 cm. by 1-5-4 cm. and their texture is rathe/ thin. 



7. Botteri, no. 831, Pebr. 1854, Orizaba. A fruiting 

 Lranch; leaves elliptic-oblong to oblong, obtuse, crenate, rather 

 iomentose beueatli, up to 4 cm. by almost 3 cm. 



Morelos. 8. C. G. Pringle, no. 6983, fields about Tepoxtlan 

 (2250 m.) ; a large tree. Plowering branch with mostly broad- 

 oblong and obtuse or acute leaves with small crenae and 



foliaceous cultriform stipules, blades 4-8 cm. by 2-5-4 cm. 

 Barren armed branch with smaller, more acute and,'^lower down, 

 narrower almost oblaiiceolate leaves. Similar foliage occurs in 

 the Kew tree, except that the crenation is rarely so minute. 



We thus find that the Mexican hawthorn of European gardeiis 

 occurs in a practically identical condition within the natural area 

 of Crataegus imhescens (Mespilus pubescens, II.B.K.), while 

 forms more or less lilvP it extend beyond it on to the outer slopes of 

 the Mexu\in table-land. But we have at present no means of work- 

 ing out the genetic relations that exist between tliis f. .^tipulacea 

 and the original C. puhescens, that is, the f . Hnmholdtii on the one 

 hand and the modifications which are covered by some of the speci- 

 mens mentioned above (1-8). There occurs no doubt a good deal of 

 variation in the same individual, probably mainly duo to condi- 

 -iious of nutrition and insolation, and it may be assumed that the 



