December 27, 1917] 



NATURE 



pages of description of macroscopic appear- 

 ances. 



It is to be reg^retted that in a work of this 

 character there should appear several slips due to 

 lack of care in revision. On p. 2\ it is stated 

 quite rightly that "in birds with more marked 

 binocular vision — hawks, for example — the iem- 

 poral fovea has the greater depth and the eye 

 becomes more asymmetrical"; and further on, 

 on the same page: " Steieoscopic, binocular, 

 single vision in birds with double foveas ... is 

 probably accomplished by the two temporal foveae 

 acting in cerebral unison." Yet on p. 56, speak- 

 ing of the birds of prey in general and the 

 sparrowhawk in particular, the author states that 

 "the 7iasal fovea is invariably the deeper and 

 sharper of the two, and probably is used when 

 distinct sight and binocular vision are required." 

 On pp. 12 and 44 the author uses the term 

 vcurilenima where obviously he is referring to the 

 myelin sheath of the nerve-fibre, and on p. 22 he 

 uses the same term neurilemma ior the pial sheath 

 oi the optic nerve. We believe that some physio- 

 logical writers of past ages did call the peri- 

 neurium neurilemma, but from the time of 

 Schwann onwards the word has had a definite 

 restriction to the outer sheath of the nerve-fibre, 

 and to that alone. 



It is only the interest with which we have read 

 Dr. Wood's book that has led us to note these 

 I minor faults, and we must conclude with a note 

 I of admiration for the beautifully coloured repro- 

 ductions of Mr. Head's drawings of the fundi of 

 many different species of birds. 



.4 NATURALIST IN COSTA RICA. 

 A Year of Costa Rican Natural History. By 

 Amelia S. Calvert and Prof. P, P. Calvert. 

 Pp. xix + 577. (New York: The Macmillan 

 Co.; London: Macmillan and Co., Ltd., 1917.) 

 Price 125, 6d. net. 



PROF. CALVERT, after several prolonged 

 journeys to Mexico and other countries, has 

 extended his entomological studies to Costa Rica, 

 in which State he has spent a whole year, from 

 May, 1909 to 1910, accompanied by Airs. Calvert, 

 likewise a keen naturalist. Their chief purpose 

 was a study of the dragonflies with reference to 

 their seasonal distfibution, which necessitated 

 visits to the same localities at different times 

 throughout the year. These special investigations 

 having not yet been completed (Appendix iii. con- 

 tains a long list of papers based on the collec- 

 tions, written by the authors and other specialists), 

 their results are deferred, and the present book, 

 embellished with some 150 illustrations, mainly 

 of plants and insects, is devoted to the thousands 

 of observations of all kinds of animals and plants 

 as the travellers came across them. Here lies the 

 drawback of the book ; although so full of in- 

 formation, there are but few chapters to be enjoyed 

 by the general reader, who. taking the detail, 

 much of which is unavoidably technical, for 

 NO. 2513, VOL. 100] 



gt anted, would relish some more comprehensive 

 generalised descriptions as characteristic of the 

 country. 



Most of their time, about nine months, was 

 spent, off and on, at Cartago, near the capital, 

 San jps6, situated in the centre of the State, 

 10° N., at an altitude of some 4700 ft. Cartago 

 is a very important place; there •was to have been 

 inaugurated in June, 1910, the "Central American 

 Court of Justice," i.e. Carnegie's Peace Palace. 

 From the naturalist's point of view the district was 

 eminently well selected to serve as headquarters, 

 situated as it is on the backbone of the country, 

 at an altitude delightful for a country in the 

 tropics, well watered by numerous streams, well 

 wooded and very fertile, and last, not least, con- 

 nected by the railway with the Atlantic and the 

 Pacific. Thus they were enabled to make excur- 

 sions through and into the most diverse kinds of 

 country. 



Irazu, the highest volcano, 11,300 ft., now 

 extinct. Or rather dormant, like so many Central 

 American volcanoes, is only some ten miles from 

 Cartago. Tt was visited several times, and on 

 one occasion our naturalists spent a night in the 

 crater with a tent. This chapter, well illustrated 

 with photographs, contains a lively, graphic 

 description of the altitudinal and other charmingly 

 interesting changes. 



The Costa Rican Government obliged them by 

 numerous acts of courteous assistance. On 

 several occasions Prof. Calvert was invited to 

 join some Government commission — for instance, 

 to the north-west province — so that he acquired a 

 very satisfactory general knowledge of the middle 

 belt of the country, from the Atlantic to the 

 Pacific. 



Costa Rica is a well-to-do farming countrv ; 

 the aboriginal natives give no trouble, and the 

 other mixed and white people have the good sense 

 to keep themselves and their country out of 

 politics. Greatly helped by not a few of the 

 scientific and other residents, everything went 

 smoothly, and there were no stirring incidents of 

 travel to relate until the halcyon year of the con- 

 joint authors was brought to a sudden, cata- 

 strophic end. 



Earthquakes are endemic in Central America, 

 and more or less disagreeable shocks had been 

 not uncommon at Cartago. Within the last 

 2qo vears the town had been destroved several 

 times. On April 13, 1910, there occurred a few 

 severe shocks, increasing to three dozen bv the 

 next day and badly damaging the town ; but the 

 disturbance was so local that Prof. Calvert, who 

 happened to be only thirty miles away, did not 

 think it worth while to return to his partner, who 

 was at Cartap-o. They made the best of the 

 ensuing confusion until May 4, when some sudden, 

 terrific shocks laid the town in ruins, including 

 the Peace Palace, and two davs Inter our lucky 

 travellers, themselves unharmeH nnd withoi't nnv 

 damage to their numerous collections, left for 

 home. 



