386 Recent Literature. [June, 
mans, have utterly confounded, under one name, that which is a 
product of a cooling magma, and that which is a secondary altera- 
tion product in rocks. On page 274 he states that “ Petrology 
becomes the study of an endless cycle of changes from eruptive 
to sedimentary, and from sedimentary to eruptive rocks.” 
cycle of which the last half is oe sustained by field or 
microscopic research, nor by physic 
Such errors as picotite for die (p. 141), chrysolite for 
chrysotile (p. 271) disfigure the work. Speaking of tridymite, on 
page 152, he says, “It has also been mentioned as occurring in 
some Irish rock, but the author is unable either to recall the pre- 
cise locality or to find the reference.” 
Had he looked on the upper part of the same page! on which 
his own paper on tachylyte is published, to which he refers so 
often, he wouid have found it, as well as in numerous other scien- 
oy journals published in eee and on the continent.— 
M. E. W. 
WRIGHT'S EET TO AMERICAN HELMINTHOLOGY. — 
Packard, Minot and Fitz. Thirteen De are enumerated, of 
which five are new. One new genus (Sphyranura) is proposed, 
while Leidy’s genus C/nostomum is united with Distomum. In 
the descriptions of the species are included many anatomical facts; 
Minot’s statement that the water vascular system and pa he 
spaces are connected in Distomum is confirmed. of the 
more interesting habitats recorded are. Polystomum Saloni in 
the urinary bladder of the musk-turtle; Sphyranura oslert occurred 
in the mouth and gills of Menobranchus ener Tenia dispar in 
Rana halecina. The round worm which was so prevalent in the 
shad last spring is referred by our e Süthor to Aa adunca Rud. 
The two plates which illustrate the article are well drawn and 
printed.— F. S. K. 
SCIENTIFIC RESULTS OF THE CHESAPEAKE ZOOLOGICAL LABORA- 
TORY.*—The speedy publication and finished nature of the papers 
in this youe speaks well for the industry shown by those who 
worked at: this hastily equipped laboratory, and shows that 
saan constructed laboratories and expensive museums are 
not, from new and improved biological methods, essential the 
real advance of biology in its widest sense. It ‘will be remem- 
perma of the Royal Geological Society of Ireland. New series, Vol. 1v, Part 
4,1 
f abe ons to American enii No. oe By R. Ramsay WRIGHT. 
, No. 
(Proc. Canadian Institute. New series, Vol. 1 
3 Fohns Hopkins fiep a peta Mi i. i Zoölogical Page 
ae _Rerentific Results e Session of 1878. Organized and conducte 
(June 24 m pia 19, 1878) Baltimore, 1879. Pe pp- 170, A plates. 
