310 AORIOULTURA.L EXPERIMENT StATION, ItHAOA, N. Y. 



consequence, it is wonderfully variable. Bureau, in his mono- 

 graph of the genus in 1873, refers thirty-one described species 

 to M. alba and recognizes tv\-enty-seven botanical varieties op 

 types of it. But it is difficult, in some cases, to distinguish( 

 between M. alba and M. nigi-a, and if we are to follow Bureau's 

 clas«^ification I do not see how the two can be kept apart, fop 

 some of the plants which he refers to M. alba seem to be las distinct 

 from its type as M. nigra is. In this paper I have kept apart 

 two species which are commonly referred to Moras alba. I do 

 not know if they are distinct species, but they are more easily 

 understood if they stand by themselves; and as species at best 

 are only judgments of the particular author who describes themi 

 and not entities in nature, I may be allowed the present arrange- 

 ment. 



The later American mulberry culture for fruit, scant as it is, 

 has developed along independent lines. The black mulberry. 

 Moras nigra, is the fruit-bearing mulberry of history, and nearly 

 all writers declare that the Avhite mulberry possesses little or no 

 value for frait. Yet in America the black mulberry is almost 

 unknown, except sparingly in the south and in California, and 

 some of our common varieties are offspring of the white mulberiy. 

 And to these must be added varieties which I am satisfied belong 

 to our native red mulbeiTy. 



The American mulberries, so far as I know them, may be 

 grouped under the following species, omitting the kinds which, 

 were early cultivated for silk and are now practically unknown 

 in the country: 



1. The White Mulberry group. — Moras alba. 



1. (a). Russian Mulberry. — Var. Tatarica. 



1. (b). Nervosa mulberry. — Var. venosa. 



2. The Multicaulis group. — Moras latifolia. 



3. The Japanese group. — Moras Japonica. 



4. The Black Mulberry group. — Moras nigra. 



5. The Red or Native Mulberry group. — Morns rubra. 

 5. (a). Lampasas mulberry. — Var. tomentosa. 



1. The White Mulberry group. — (Morns alba, Linn.) Leaves 

 light green, rather small, smooth or very nearly so above and| 



