NEW SPECIES KOSSIL CONIFEROUS WOOD 



The specimens in this collection have all proved to be coniferous at 

 to belong to the genus Cupressinoxylon.* The first species I nil 

 named, in honor of the collector: 



Cupressiiioxylon Glasgowi, n. sp. Plate n, figs. 1-5. 



Diagnosis.— Annual rings very sharply marked, 3 to 44""" broa> 

 tracheitis in the summer wood provided on the radial walls with one] 

 two series of very large bordered pits 5 medullary rays numerous, o I 

 to 30 superimposed cells in a single series, resin ducts moderat< 

 numerous, of a chain of short cells. 



Locality, Emmet County, Iowa. Horizon probably Cretaceous. 



MICROSCOPIC ANALYSIS. 



Transverse section. — The annual rings as observed in this section a 

 very apparent to the naked eve, the actual ring or line of separata 

 being a brown band nearly a millimeter in width, while the whole wid 

 of a ring, as stated above, is often more than 4""". Under the mic: 

 scope the cells are shown to be arranged in strict radial rows, and t 

 band above mentioned is found to consist of a layer of from 18 to 

 cells more or less completely liguified. In the outer layers of this 1 

 nilied band of fall-wood the lumeu of the cells is reduced to a minimu 

 The lumen is in the form of an ellipse of which the long diameter is le 

 than .01 mm and the short diameter about .005 mm . Iu the immediate 

 following layer of spring-wood the cells are very large and thin-walk' 

 measuring .08""" in long, and .05 mm in short, diameter. In the sumnx 

 wood the cells become smaller and more nearly hexagonal in outlii 

 and pass abruptly into the baud of fall-wood. 



Radial section.— In this section, as in the transverse, the deinark 

 tion between fall and spring wood is very clearly marked (PI. 11, fi$ 

 1, 4, 5.) The walls of the cells in the spring and summer wood are the on 

 ones provided with bordered pits, and in these they seem not to ha^ 

 been very abundant, or at least are not preserved in a maimer capab 

 of demonstration. These pits are usually arranged in two paral 

 rows, although in some cases there is but one row, when it occupies tl 

 center of the cell. The pits are large, and when in two rows take ] 

 nearly the entire width of the cell. The diameter of the outer circle 

 in extreme cases fully .0250""", the average being about .0200"""; tl 

 diameter of the inner circle is only .0025 to .0040 nnu . 



The medullary rays are observed to be numerous, with the individu; 

 cells very long. The individual cells are not, however, very high, J 

 they are thin-walled. They have not been provided with border^ 

 pits, or at least none are preserved. 



The resin-ducts have been moderately numerous. They are compose 

 of a c hain of short thin walled cells from .15""" to .25""" in length an 



•Many authors write Cipressoxylon, but as I re S *rd~Cup>^mnew as the root fr| 

 whicb the word is formed I prefer to write Cupresainoxylon. 



