1898] - SOME NEW BOOKS 351 



articles of this description. The illustrated development of the trout 

 is pedantically described as its ' evolution,' and its yolk-sac is inac- 

 curately placed. A two-year-old trout, we are told, passed an 

 accidental sojourn in a ' fry -pond ' for a few months, and lived up 

 to his privileges to the extent of devouring 30,000 fry. Those 

 who are prepared to accept this statement will, we do not hesitate 

 to state, cry ' enough ' when told that the weight of this ' two- 

 year-old' increased during that period from 6 oz. to of lbs. 

 The article is beautifully illustrated, and cannot fail to interest. 

 We cannot say the same of the extraordinary literary effort on 

 " Human Nails and Horns," preceding it. Here the author audaciously 

 describes everything from a human wart to a deer's antler as a ' horn,' 

 apparently considering that the authority of the Boston Medical 

 Journal and the like is sufficient to allow his artist to give free vent 

 to his imagination. He remarks : " The whole subject is one highly 

 deserving of attention from the naturalist or the philosopher." Speak- 

 ing from the point of view of the former, we think we may safely pass 

 this article on to the latter ! 



We continue to receive copies of interesting papers from Mr T. H. 

 Holland, now officiating Superintendent of the Geological Survey of 

 India. The latest is " On a Quartz-Barytes rock occurring in the 

 Salem district, Madras Presidency " {Records Gcol. Surv., India, vol. 

 XXX. pp. 234-242, pi. xviii., 1897). The rock forms a network 

 of veins in gneissic rocks. The veins, which vary considerably in 

 size, occupy fissures inclined at all angles to the horizon, and are com- 

 posed of quartz and barytes in the proportion of 7 to 3. In the rock 

 there are also found small quantities of accessory minerals, such as 

 galena, pyrites, ilmenite, and hematite, which carry a small proportion 

 of gold, 13 grains to tlie ton. The barytes is well crystallised, often 

 forming large individuals, and this, as the author points out, is also 

 the case even in veins of the smallest dimensions. The quartz is seen 

 under] the microscope to consist of an aggregate of irregularly inter- 

 locking crystals, wliicli are sometimes quite microscopic. The author's 

 conclusion is that Ijoth the quartz and barytes are original constituents, 

 which have separated out from an injected mobile magma, the barytes 

 being the first to crystallise. He rejects another possible explanation, 

 namely, the derivation of the rock from a pegmatite (barytes replacing 

 felspar by pseudomorphism), on the ground that the proportion of 

 c[uartz to felspar in the graphic pegmatites is quite different ; more- 

 over, there are no traces of any material after which the barytes might 

 he pseudomorphous. 



The John Hopkins University Circular for November 1897, is 

 melancholy reading, for in it Prof. W. K. Brooks has to tell the story 

 of the students' expedition to Jamaica in the summer of 1897, and 

 its tragical end. A party had been formed, under the charge of 

 Prof. J. E. Humphrey, for the purpose of botanical and geological 

 research, and they set up a temporary laboratory at Port Antonio. 

 Here two months' good work was done, and Prof. Humphrey, with 

 Drs Conant and Clark, and Mr Fredholm, had seen all the younger 

 members of the party safely started for home, when the former was 

 suddenly struck down by fever, and died on August 17th, after a few 



