January 30, 1891.] 



SCIENCE. 



67 



to 5,000 metres will be higher than the temperature observed at 

 the earth's surface. 



Taking the average decrease of temperature vcith height founrl 

 from the observations on Pike's Peak and Mount Washington, and 

 usmg the temperature and pressure recorded at stations on the 

 daily weather-chart, I have, by Kbppen's method, calculated the 

 pressure at the height of 5,000 metres above a large number of 

 areas of high pressure, and drawn isobars for this height. These 

 show that above the larger number of winter anticyclones on our 

 Western plains the pressure is lower than on the same latitude 

 farther east. Even if we malie the extreme assumption that there 

 is no decrease of temperature above these anticyclones up to 5,000 

 metres, some of the cases will still show a lower pressure at this 

 height than on the same latitude on each side. In these cases 

 there seems no escape from the conclusion that the pressure at the 

 earth's surface is due chiefly or entirely to the low temperature of 

 the air. But there are other cases of anticyclones over these plains 

 in the summer-time, and of anticyclones on our seacoast in win- 

 ter, in -which the temperature is as high as, or higher than, near 

 the earth's surface within the aoticyclones as on the same latitude 

 farther west. In these cases it is sometimes difficult to get a 

 lower pressure in the upper air above them, even though we 

 assume the adiabatic rate of cooling. Moreover. I know that 

 these high pressures on rare occasions extend up even to the cir- 

 rus region, for I have observed cirrus-clouds moving out from 

 them toward the west in their south-west quadrant as the surface 

 wind does near the earth. I am hence led to believe that there 

 are two classes of anticyclones, — one due chiefly or entirely to low 

 temperature, and the other due chiefly or entirely to dynamic 

 causes. It seems to me probable that the same is true of cyclones. 



H. Helm Clayton. 



Blue Hill Observatory, Jan. 22. 



Questions of Nomenclature. 



Professor C. S. Sargent, author of the " Silva of North 

 America," says, in the tirst volume of that work, " I have adopted 

 the method which imposes upon a plant the oldest generic name 

 applied to it by Linnseus in the first edition of the ' Genera Plan- 

 tarum,' published in 1737, or by any subsequent author, and the 

 oldest specific name used by Linnaeus in the first edition of 

 ' Species Plantarum,' published in 17.53, or by any subsequent 

 author, without regard to the fact that such a specific name may 

 have been associated at first with a generic name improperly 

 employed." 



To secure stability in nomenclature, it is obvious that the 

 method adopted by Professor Sargent is the one which should uni- 

 versally be adopted by botanists. Other questions relating to 

 botanical nomenclature are not so well settled as might be desired, 

 and a few of these may be briefly stated, with the writer's present 

 views concerning them. 



The first in importance, perhaps, is the use of the names of 

 forms at first described as varieties of other species, and later 

 raised to specific rank, or vice versa. It would seem that the 

 varietal name as first used should be adopted for the specific name 

 when raised to specific rank, though many botanists have felt at 

 liberty to rechristen them at pleasure. A varietal or subspecific 

 name would, if this rule were followed, receive precedence over 

 later names. Professor E. L. Greene, in " West American Oaks," 

 has adopted the name Querciis Palmeri Engelm. in preference to 

 Q. Dunnii Kell., although first published as a species under the 

 latter name, Q. Palmeri having first been published as a sub- 

 species by Dr. Engelmann, and later as a species. One is led to 

 infer by Professor Greene's remarks, that, had Q. Palmeri been 

 published as a variety instead of as a subspecies, he would have 

 adopted Kellogg's name for the species, though why such a dis- 

 tinction is made is not very evident. 



Bentham, in fact, held that the earliest published name, whether 

 applied as a specific or varietal, belonged inalienably to that in- 

 dividual form, whether subsequently redescribed and ra:^ed to 

 specific, or degraded to varietal rank. 



" Once a synonyme always a synonyme," is a rule which I be- 

 lieve obtains among zoologists in general, and should, if tenable 



with them, be adopted by botanists as well. This would necessi- 

 tate some important changes if adopted; and as an instance may 

 be noted the genus Washingtoaia, now in use for our Californian 

 fan-palms, a synonytne of Sequoia, having been unfortunately 

 applied to our Californian giant before its application by Wend- 

 land to our palm. 



If the facts permitted, some enterprising botanist might see fit 

 to reinstate the coniferous genus, in which case the genus of 

 palms would of necessity have to be renamed. Still, it seems like 

 creating needless synonymy in this case to rechristen Wendland's 

 genus, though strict adherence to the rule would render it imper- 

 ative. 



Uniformity in the method of citing the authors of species is 

 another desideratum in botanical nomenclature. The most ex- 

 plicit custom is that adopted in general by zoologists, — the en- 

 closing in parentheses the name of the author of the species or 

 variety, where originally given wrong rank, or referred to a 

 genus incorrectly. While this is often cumbersome, yet it greatly 

 facilitates subsequelit work beyond question,' and is preferable to 

 the citing of the name of the author who has referred the plant in 

 question to a different genus, or considered it as of different rank. 

 The existing confusion in the manner of citations renders it im- 

 possible for a writer to do strict justice to the founders of species, 

 unless he is favored with access to large botanical libraries, and 

 blessed with abundant leisure for consulting original descriptions. 

 The author of the species (or variety), it seems to the writer, is 

 the one to be cited (if the system of double citation is discarded as 

 inconvenient) in preference to the authority for its transferrence 

 from one genus to another. 



Another point upon which botanists ax-e not fully agreed is the 

 citation of names adopted in manuscripts or herbaria, and receiv- 

 ing earliest publication by others than their authors. It is the 

 custom in America (and a sensible custom it is) to cite the real 

 author's name, even when first described and published by another 

 author (unless published by that author as of his own authorship). 

 Thus, Nuttall is credited with the authorship of many genera and 

 species first described by Torrey & Gray in the "Synoptical 

 Flora," or by DeCandoIle or others elsewhere. 



It is now generally conceded that an author, after publishing a 

 name, has no longer any right to substitute another name there- 

 for in subsequent publications, even though the first name he 

 finds to be a misnomer. This right, claimed by many of the older 

 botanists of a past generation, is no longer contended for. It is 

 also an open question as to how far published names may be 

 changed or corrected by their own or subsequent authors. 



A common Californian cactus is published by Prince Salm in 

 " CactesB Horto Dyckensi," p. 91, as Mamiliaria Goodrichii 

 Scheer, named in honor of Mr. Goodrich. Professor Sereno 

 Watson informs me that Seemann says in the " Botany of the 

 'Herald'" that it was a "Mr. J. Goodridge, surgeon," whom the 

 plant was intended to commemorate in its name as its discoverer. 

 The name, therefore, has been written M. Qoodridgii by many 

 subsequent authors. Gray (Botanical Oazette, ix. 53) inadvert- 

 ently publishes Antirrhinum Nivenianum, and repeats this spell- 

 ing on the following page. This was collected by Rev. J. C. 

 Nevin, and it is obviously proper to write A. Nevinanuvi, as the 

 former spelling was mere inadvertence or a typographical error. 

 But in the instance of Mamiliaria Goodrichii, as originally written 

 there is less cause for change, since the man may not have been 

 clear in his own mind as to the coiTect spelling of his name, — 

 like Shakspeare, spelling it differently at different times. 



C. R. Orcdtt. 

 San Diego, Cal., Jan. 20. 



BOOK-REVIEWS. 



Inwganic Chemistry. By William Jago. London and New 

 York, Longmans. 12°. SI. 50. 

 This text-book is intended to meet certain conditions of science- 

 teaching prevalent in Great Britain, due to the work going on 

 under the auspices of tlie Science and Art Department. It is a 

 more advanced book than the author's " Elementary Text-Book " 

 on the same subject, issued some time ago. The supervision of 



