58 MISC. PUBLICATION 42 3, U. S. DEPT. OF AGRICULTURE 



44. Styles 2, or single and 2-cleft; plants mostly pu- 

 bescent; leaf blades seldom entire ; inflorescence 

 commonly scorpioid_ 105. Hydrophyllaceae. 

 42. Ovary with 2 or more cells or, if 2-celled only at base 

 (in genus Limosella), then the plant a small semi- 

 aquatic herb with small solitary flowers, a 5-lobed 

 corolla, and 4 stamens (45) . 

 45. Fruit a circumscissile capsule; flowers small, in 

 dense terminal spikes. _ 115. Plantaginaceae. 

 45. Fruit not circumscissile (46). 



46. Plants shrubby; flowers small, in dense axillary 

 clusters, these often forming leafy interrupted 



spikes: 99. Loganiaceae. 



46. Plants herbaceous or suffrutescent or, if shrubby, 

 then the flowers solitary or in few-flowered 

 loose axillary clusters, in genus Lycimn, or in scor- 

 pioid terminal racemes, in genus Eriodictyon 

 (47). 

 47. Stigmas 3; style 1, often 3-cleft. 



104. POLEMONIACEAE. 



47. Stigmas 1 or 2, or sometimes 4 in family Con- 



volvulaceae (48). 



48. Styles 2, entire or cleft, or the style 1, 



"2-cleft (49). 



49. Ovules 2 in each cell of the ovary; stems 



often twining; flowers not in scorpioid 



racemes 103. Convolvulaceae. 



49. Ovules more than 2 in each cell; stems 



never twining; flowers often in scor- 

 pioid racemes. 



105. Hydrophyllaceae. 

 48. Style 1, entire (50). 



50. Ovules 2 in each cell of the ovary. 



103. Convolvulaceae. 



50. Ovules several or many in each cell of the 



ovary (51). 



51. Anther-bearing stamens normally 5 or, 



if 4 and a rudimentary stamen present, 



then the flowers lateral, solitary, or in 



small clusters; inflorescence never an 



elongate terminal spike. 



109. SOLANACEAE. 



51. Anther-bearing stamens 2 or 4 or, if 5, 

 then the inflorescence an elongate 

 terminal spike. 



110. SCROPHULARIACEAE 



1. PINACEAE. Pine family 



Trees or shrubs, resinous; leaves evergreen, needle-shaped, narrowly 

 linear, or else scalelike, crowded, and imbricate; flowers unisexual; 

 perianth none; staminate inflorescences with numerous spirally 

 arranged stamens; pistillate inflorescences with scales arranged 

 spirally or in pairs alternately crossing at right angles (decussate), 

 these bearing at base 2 or several naked ovules ; fruits in cones, these 

 sometimes berrylike. 



Key to the genera 



1. Leaves in the adult state closely imbricate, minute, scalelike or, if not closely 



imbricate and scalelike, then the cones berrylike, juicy; scales of the 



pistillate flowers without bracts (2). 



2. Cones globular, dry at maturity, the scales woody and finally separating, the 



cones long-persistent on the branches after the seeds have fallen; seeds 



numerous under each scale, winged 5. Cupressus. 



