SECRETARY'S REPORT. Q^J 



next, Flowerless plants, called Cryptogamia, which have neither 

 flowers nor seeds, but are propagated by means of little bodies of 

 homogeneous structure, and not containing any embryo. Among 

 these are the mosses, lichens, ferns, (commonly called brakes,) 

 mushrooms, &c., &c. Phfenogamia or flowering plants, are next 

 divided into two classes, based on the fact that in one the plants 

 grow by accretions to the outside, and in the other they grow from 

 the inside, crowding outwards. The first of these is called Exoge- 

 nous, signifying outside growers. Cut off" smoothly a twig from a 

 rose bush or a limb from an apple tree, and you find it made up of 

 bark, wood and pith, and that the limb has increased by additions 

 to the outside. Plants of this class have seeds made up of two flat 

 or rounded pieces fitting closely to each other, called seed leaves, 

 lobes, or cotyledons, and are therefore called di-cotyledonoiis. They 

 may also be recognized by examining the leaves, which have mtted 

 veins. Nearly all trees in cold and temperate latitudes belong to 

 this class. The second class is called Endogenous, signifying 

 i7iside grorcey^s. If we cut a corn stalk or a stem of asparagus or 

 a palm tree, if we were where the palm grows, we find an entirely 

 different structure from what prevails in the outside growers. The 

 inside is not divided into bark, wood and pith, but is all alike, and 

 does its growing from the inside, crowding outwards the expanding 

 covering of the stalk. The seeds of this class have but one lobe or 

 cotyledon, as we see in a grain of wheat or kernel of corn, and are 

 therefore called tnono-cotyledonons. Plants of this class have 

 leaves with parallel veins. It includes all the grasses, properly so 

 called. Clover, which is spoken of in common language as a grass, 

 is not one in a botanical sense, as it belonsrs to the class exogens, 

 having a seed with two lobes and netted veins. 



These two classes are next separated into a few Sub-classes, 

 and these into many Orders; the orders into Genera, of which 

 each genus may be composed of one or of many Species, and each 

 species into more or less varieties, which is the lowest grade of sub- 

 division, unless it be into individuals. 



The Grasses (Graraineas) are an order ; the Phleum, Agrostis, 

 Poa, &c., are each a genus. Phleum pratense, (Ilerdsgrass,) 

 Agrostis vulgaris, (Redtop,) Poa pratensis, (June grass,) are each 

 a species of their several genera, the Phleum, Agrostis and Poa. 



