564. Reviews—Conrad’s Fossil Shells. 
of this latter is penetrated just below the line of junction for about 
1 m. in depth, by pockets and branching cylindrical or elliptical 
pipes filled with rich phosphatic chalk, and in places there is an 
apparent breccia between the two beds, in which the fragments of 
White Chalk have sharp angles, and form but a small proportion of 
the whole mass. 
The gray bed of phosphatic chalk is overlaid in places also by 
White Chalk in which there are likewise some grains of phosphate, 
in places by Tertiary deposits. In some areas the gray bed crops 
out near the surface, and it then sometimes contains pockets of 
phosphatic sand. 
IJ.—Repvsiication or Conrap’s Fosstz SHELts oF Ton TERTIARY 
_ Formations oF Nort America. By G. D. Harris. (Washing- 
ton, 1893.) 
Repusiication or Conrap’s Fossits or tHE Mepran Tertiary 
or THE Unitep States. With an Introduction by Dr. W. H. 
Datt. (Philadelphia, 1893.) 
ites republishing the above works of Conrad, Messrs. Dall and 
Harris have rendered an immense service to students of the 
Mollusca. The first mentioned book was published in parts, which 
only exist at the present day in a more or less fragmentary condition. 
The dates of their issue were practically unknown until Dr. Dall, 
with infinite pains and research, succeeded in establishing the same;' 
whilst Mr, Harris was subsequently enabled to make some further notes 
thereon.” The former author remarks that ‘Mr. Conrad had several 
peculiarities ; he wrote his letters and labels frequently on all sorts 
of scraps of paper, generally without date or location. He was 
naturally careless or unmethodical, and his citations of other authors’ 
works cannot safely be trusted without verification, and are usually 
incomplete. He had a very poor memory, and on several occasions 
had re-described his own species. This defect increased with age, 
and, while no question of wilful misstatement need arise, made it 
impossible to place implicit confidence in his own recollections of 
such matters as dates of publication.” 
Conrad’s method of publication, too, was slovenly in the extreme. 
The ‘‘ Medial Tertiary’ volume, also issued in parts, had blank 
spaces left on the covers for the purpose of filling in the number of 
each part and the date of its publication—these particulars being 
written with a pen, presumably by the author. Sometimes when 
there were a few diagnoses over, enough to fill a ‘“‘signature” of 8 
or 16 pages, the excess was printed on the cover, and occasionally 
the cover of one and the same part was twice surcharged. It would 
seem from Dr. Dall’s observations that the sheets were kept on hand 
and made up into a volume when called for from time to time by 
the subscribers. In regard to the plates in the work, it appears 
that, owing to the vagaries of the authors, there is at least one plate 
1 Bull. Phil. Soc. Wash. vol. xii. (1893), pp. 215-239. 
2 American Geologist, vol. xi. (1898), p. 279. 
