90 THE AMERICAN UOTANIST. 



T3'-phacese, the SparganiacejE and the Pandanacear, there 

 are but five genera and a very limited number of species, 

 all of them water-loving plants. 



The screw-pines and their allies inthePandanacea^ are 

 shrubs and trees found in the Tropics of the Old World. 

 Our representatives of the order are the cat-tails and burr- 

 reeds of our marshes and swamps. Not so long ago, all 

 were placed in a single fiimUy, the Typhacete, but the3' are 

 now prett3^ generally regarded as distinct enough to form 

 two families of equal rank. In the Typhace^E there is but 

 a single genus, Typha, and about a dozen species, while 

 the Sparganiace^, has the single genus Sparganium and 

 about the same number of species. 



As befits the most primitive of the Angiosperms, the 

 flowers are very simple structures. In the Typhacese they 

 are assembled in spikes, and in the Sparganiaceas in heads 

 and these are subtended by scarious spathe-like bracts 

 that doubtless foreshadow the spathes so noticeable in 

 the Arum family. In the cat-tails the staminate flowers 

 are borne above the pistillate ones and on the same axis. 

 They consist normally of three stamens surrounded b}- 

 various slender bristles which by some botanists are taken 

 to represent a cah'x and corolla. The pistillate flowers, 

 also assembled in spikes, each consist of a single ovary 

 elevated on a thread-like stalk called a g^-nophore. In 

 some cases each pistil is surrounded by atinyspathe. Be- 

 low^ the ovary the g^-nophore produces numerous hairs 

 which as in the case of the stamens are often considered 

 to be a rudimentary perianth. The stamens ripen just as 

 the pistils are receptive and self-pollination seems to be 

 unavoidable. The pollen is shed in prodigious quantities 

 and in some parts of the world is used as food. It has 

 also been used like L^xopodium spores. 



Sparganium differs from Typha in having both sta- 

 mens and pistils in heads, ])ut the staminate flowers are 

 as usual above the pistillate and self-pollination is the rule. 

 It is likely, however, that the flowers are occasionl}' cross- 

 pollinated b\' insects since both sorts of flowers are fairl)' 



