applications of achene data are contradictory (Emboden, 1974; 
Small and Cronquist, 1976). 
Recent proponents of the monotypic view of Cannabis (Small 
and Conquist, 1976) emphasize chemical data and interfertility of 
the plants. Data from hybridization experiments are sometimes 
over-emphasized. Those which can be achieved through artificial 
hybridization in the garden or greenhouse often give an 
exaggerated view of biological interactions among natural 
populations. In general, interspecific hybridization is a relatively 
frequent phenomenon (Knoblock, 1959), especially so in wind- 
pollinated species such as Cannabis. The ability to hybridize or 
not is not recommended as a sole or major species criterion, 
because the degree of fertility among interspecific hybrids varies 
widely (Stace, 1975). This is particularly true for many weedy 
plants (like Cannabis); Baker (1972) states: “A full spectrum of 
interspecific hybridization can be seen in the world’s weed flora, 
from the formation of sterile F; hybrids to the production of 
vigorous, fertile amphidiploids or significant introgression.” 
Species of Cannabis are not mutually exclusive in their 
cannabinoid content, and cannabinoids are known to fluctuate in 
quantity and composition during the life cycle of the plant. 
Consequently, a study group sponsored by the United Nations 
Narcotics Laboratory (1976) stated that “cannabinoid composi- 
tion can serve only as a limited chemotaxonomic tool.” Turner ef 
al. (1973) demonstrated that cannabinoid composition is not 
stable in stored plant material, and Turner (pers. comm.) has 
noted daily fluctuations in cannabinoid content in living plants. 
Therefore, a single plant might be classified with Small and 
Cronquist’s key (1976) as C. sativa ssp. sativa at one time of day 
and as C. sativa ssp. indica at another time of day! Clearly the use 
of chemical data as primary taxonomic criteria (Small and 
Cronquist, 1976) is neither practical nor natural and has been 
duly criticized by Emboden (1977). 
Judging from Small’s annotations on herbarium sheets, his 
predilection to classify plants by intoxicant ability and/or 
geographical distribution has resulted in placing many plants of 
C. sativa in with C. indica. Consequently, the two groups would 
then not represent distinctive morphological forms (perhaps this 
contributed to his recognition of the groups as subspecies rather 
68 
