August 1, 1913] 



SCIENCE 



165 



sporophylls. The ovules have a bright orange 

 color. 



The taxonomic descriptions of the four Aus- 

 tralian species of Cycas are very incomplete, 

 but may be sufiicient for identification. All 

 the species grow in the omnipresent but scanty 

 eucalyptus bush, often associated with 

 Xanthorhiza, Pandanus and Macrozamia. 



Material has been secured for a complete 

 morphological study, including the anatomy 

 of the adult plant and the seedling. 



The most peculiar of the Australian cycads 

 is Bowenia, whose bipinnate leaves readily dis- 

 tinguish it from all other cycads. There are 

 two species, Bowenia spectabilis, which is 

 abundant in the northern part of Queensland, 

 about Cooktovra, Cairns and Innesfail; and 

 B. serrulata, which is at its best in the neigh- 

 borhood of Eockhampton, about 700 miles 

 south of Cairns. The range of the species 

 could not be determined, but from the reports 

 of directors of botanical gardens, amateur 

 botanists and others, there seems to be a con- 

 siderable region between the Eockhampton 

 and Cairns districts, where neither species has 

 been found. Bowenia spectabilis has only a 

 few leaves, but they have a deep green color 

 and retain their beauty long after they have 

 been cut from the plant. Bowenia serrulata 

 has a much greater display of foliage and, in 

 some places, is so abundant that it forms a 

 dense, but easily penetrated underbrush. 



The stems of both species are subterranean, 

 so that one of the most striking differences 

 between them might be overlooked. The stem 

 of B. spectabilis is elongated and fusiform, 

 while that of B. serrulata is nearly spherical. 

 In both, the leaves are borne on branches from 

 the top of the stem. 



Macrozamia, with more than a dozen spe- 

 cies, is the dominant genus, and it ranges 

 from the northern part of Queensland to the 

 southern limit cycads in New South Wales, 

 and has at least one species in western Aus- 

 tralia. 



Most of the species have tuberous, subter- 

 ranean stems. Among these species, M. spira- 

 lis is probably the most abundant and widely 

 distributed. It is generally believed that spe- 



cies in cycads are rather fixed, but a study 

 of this species and associated species would 

 soon convince one that there is great varia- 

 tion and, perhaps, mutation. Some of the 

 species, like M. Miquelii, closely resemble M. 

 spiralis; while others, like M. heteromera, 

 bear less resemblance; but nevertheless, speci- 

 mens of these two species could be selected 

 which so closely resemble each other, that some 

 call them both M. spiralis. 



M. corallipes, M. Fawcetti and M. Paulo- 

 Guilelmi rather closely resemble M. spiralis. 

 A field study of several species warrants the 

 suggestion that M. spiralis is the source from 

 which the rest of the tuberous species have 

 been derived. 



There are only three species with tall, cylin- 

 drical trunks, and these are so distinct that 

 they are easily recognized at a glance. All 

 three species are found in Queensland — M. 

 Denisoni, on Tambourine Mountain near 

 Brisbane, is regarded by Eichler as the most 

 beautiful species of the genus. The ovulate 

 cones are nearly a meter long and reach a 

 weight of 35 kilos. The seeds are so large 

 that they are used as match boxes. Macro- 

 zamia Moorei, almost on the Tropic of Capri- 

 corn, at Springsure, is of more than ordinary 

 interest on account of its close resemblance to 

 the Mesozoic Bennettitales. Unfortunately, 

 the leaves of this species, like those of most 

 cycads, contain a poison which is very disas- 

 trous to cattle; consequently, cattlemen are 

 trying to exterminate the plant, and are suc- 

 ceeding so well — or, from another standpoint, 

 so badly — that in a few years it may be im- 

 possible to get a specimen for a conservatory. 

 They poison the plant by chopping a notch 

 and injecting arsenic into the pith. 



Macrozamia Hopei, in the Cairns district, 

 is the tallest of all cycads. I did not see it, 

 except in cultivation, but Dr. F. M. Bailey 

 told me that the statement in his " Flora of 

 Queensland " that the species reaches a height 

 of 60 feet (about 18 meters) is based upon re- 

 liable information. 



Material, photographs and notes for an ex- 

 tended study of all the Australian genera and 

 most of the species have already been secured. 



