ECONOMIC WOODS OF THE UNITED STATES 



135 



TABLE VII 



Indigenous Woods with Vessel Perforations Exclusively or Pre- 

 dominantly Simple 



Acerace^b 



Acer 

 Anacardiace^i 



Cotiims 



Rhus 

 Anonace^; 



Anona 



Asimina 

 Betulace-e * 



Carpinus 



Ostrya 



BlGNONIACEiE 



i Catalpa 

 Chilopsis 

 Crescentia 



BORAGINACE.E 



Ehretia 



BuRSERACE^i 



Bursera 

 Cactace^i 



Cereus 



Opuntia 

 Capparidace* 



Capparis 

 Caprifoliace^i* 



Sambucus 



CoMBRETACEjB 



Buceras 



Conocarpus 



Laguncularia 



EbENACEjE 



Diospyros 



Ericace^: * 



Arbutus 



Arctostaphylos 

 EuphorbiacEjB * 



Drypetes 

 Fagace^ * 



Castanea 



Castanopsis 



Fagus 



Quercus 



HlPPOCASTANACE-E 



JZsculus 



JUGLANDACE^; 



Hicoria 

 Juglans 



LaURACEjB * 



Ocotea 

 Persea 

 Sassafras 

 Umbellaria 

 Leguminos^; 

 Acacia 

 Cercidium 

 Cercis 

 Cladrastis 

 Dalea 



Eysenhardtia 

 Gleditsia 

 Gymnocladus 

 Icthyomethia 

 Leuca?na 

 Lysiloma 

 Olneya 



Parkinsonia 



Prosopis 



Robinia 



Sophora 



Zygia 



LeITNERIACEjE 



Leitneria 



MaGNOLIACEjE * 



Magnolia 

 acuminata 



MeLIACEjE 



Swietenia 

 Morace^b 



Morus 



Toxylon 

 Oleace^b 



Chionanthus 



Fraxinus 



Osmanthus 



POLYGONACEjE 



Coccolobis 



RHAMNACEiB 



Ceanothus 

 Colubrina 

 Condalia 

 Krugiodendron 

 Reynosia 

 Rosacea * 

 Amelanchier 

 Cercocarpus 

 Chrysobalanus 

 Crataegus 

 Heteromeles 

 Lyonothamnus 



Malus 

 Prunus 

 Sorbus 

 Vauquelinia 



RuBIACEjE 



Pinckneya 



RUTACE^E 



Amyris 



Fagara 



Helietta 



Ptelea 

 Salicace^e 



Populus 



Salix 

 Sapindace^e 



Exothea 



Hypelate 



Sapindus 



Ungnaria 

 Sapotace^e 



Bumelia 



Chrysophyllum 



Sideroxylon 



SlMARUBACE^E 



Ailanthus (Nat.) 

 Simaruba 

 Tiliace^e 

 Tilia 



ULMACE.E * 



Celtis 



Planera 



Ulmus 



ZyGOPHYLLACEjE 



Guaiacum 



* With some tendency to scalariform, particularly in the region of primary wood. 



Scalariform perforations look like a grid-iron or grating with an 

 elliptical or elongated-elliptical contour. The bars, with very 

 rare exceptions, are arranged horizontally or transversely. As 

 the plane is almost invariably strongly oblique and facing the ray, 

 the structure is seen to much better advantage in radial sections 

 than in the transverse and tangential. Macerated material is 

 better still since a portion of the tilted plate is likely to be cut off 

 in sectioning. Bars may also be seen in the lumina of some of the 

 vessels in the transverse section, especially if the section is rather 

 thick. 



The number of bars in a perforation varies from very few to 



