CAPPARIDACEAE. 169 



1. Cleomella angustifolia Torr. In valley, especially in sandy or alkaline 

 soil, from Neb. and Utah to Tex. Headwaters of Clear Creek ; Julesburg. 



2. Cleomella oocarpa A. Gray. In alkaline plains and desert regions from 

 Colo, to Calif. Mesa Verde, about Rio Mancos (Brandegec). 



Order 27. ROSALES. 



Flowers regular or nearly so (actinomorphic). 



Endosperm present usually copious and fleshy ; stipules mostly wanting. 

 Herbs. 



Carpels as many as the sepals ; succulent plants. 



Fam. 61. CRASSULACEAE. 

 Carpels fewer than the sepals ; plant scarcely succulent. 



Staminodia wanting ; carpels 2 or rarely 3, distinct or only partly united. 



Fam. 62. SAXIFRAGACEAE. 

 Staminodia present ; carpels 3 or 4, wholly united into a i -celled gynoecium. 



Fam. 63. PARNASSIACEAE. 

 Shrubs or trees. 



Leaves opposite ; fruit a leathery capsule, more or less adnate to the hypan- 



thium ; stipules wanting. Fam. 64. HYDRANGIACEAE. 



Leaves alternate. 



Fruit thin-walled follicles, free from the hypanthium ; stipules present 



(Opulaster in) Fam. 66. ROSACEAE. 



Fruit a berry ; hypanthium adnate to and prolonged beyond the ovary. 



Fam. 65. GROSSULARIACEAE. 

 Endosperm wanting or scant ; stipules mostly present. 



Carpels several or numerous, or, if solitary, becoming an achene. 



Carpels distinct, free from the hypanthium ; fruit achenes, follicles or 



drupelets. Fam. 66. ROSACEAE. 



Carpels united, enclosed by and adnate to the hypanthium ; fruit a pome. 



Fam. 67. MALACEAE. 

 Carpel solitary, not becoming an achene. 



Ovary 2-ovuled ; fruit a drupe ; leaves simple. Fam. 68. AMYGDALACEAE. 

 Ovary several-ovuled ; fruit a legume ; leaves pinnately compound. 



Fam. 69. MIMOSACEAE. 

 Flowers irregular (mostly zygomorphic). 



Upper petal enclosed by the lateral ones in the bud ; corolla not papilionaceous. 



Fam. 70. CASSIACEAE. 

 Upper petal enclosing the lateral ones in bud ; corolla papilionaceous. 



Fam. 71. FABACEAE. 



Family 61. CRASSULACEAE DC. ORPINE FAMILY. 



Stamens as many as the sepals; minute herbs. i. TILLAEASTRUM. 



Stamens twice as many as the sepals ; succulent herbs. 



Flowers axillary in dense congested racemes ; petals rose-colored. 



2. CLEMENTSIA. 

 Flowers terminal, arranged in one-sided raceme-like branches. 



Carpels erect ; flowers polygamous or dioecious ; petals in ours purplish. 



3. RHODIOLA. 

 Carpels spreading ; flowers perfect ; petals in ours yellow. 4. SEDUM. 



i. TILLAEASTRUM Britton. PIGMY-WEED. 



i. Tillaeastrum aquaticum (L.) Britt. (Tillaea aquatica L. ; T. angusti- 

 folia Nutt.) On muddy shores from N. S. and Wash, to Md., La. and Lower 

 Calif. Alt. up to 10,000 ft. Twin Lakes. 



