FEBRUARY 25, 1904] 
NATURE 
401 
Apart from the Somali giraffe, which certainly differs in 
colour and marking more from all the others than do the 
latter inter se, the aforesaid tendency to a gradation (with 
many local side-developments) from the northern three- 
horned and white-stockinged to the southern two-horned 
and spot-legged type points to the advisability of regarding 
the local colour-forms as races rather than species (in the 
modern sense of both terms). It should be mentioned, how- 
ever, that at present, at all events, there is no sign of one 
local form grading into another, although subsequent dis- 
coveries may prove this to exist. 
Then comes the question, are these local forms constant 
and invariable (save for individual tendencies towards 
albinism or melanism)? Dealing solely with available 
facts, and not admitting hypothesis, the answer to this, so 
far as our present information goes, is in the affirmative. 
Of course, additional specimens of each form are desirable, 
but all the examples of each type at present available point 
to the conclusion that such types are constant locally, and 
it is therefore obvious that it is incumbent on those who 
dispute this assertion to substantiate their objections by 
producing specimens showing individual variation in one 
and the same locality. 
As regards the evidence for constancy of local type, it may 
be mentioned that the herd of Nubian giraffes formerly in 
the Zoological Society’s Gardens, together with the 
numerous specimens that have of late years been imported 
into Europe, are amply sufficient to demonstrate the absence 
of individual variation in this case. The proof of constancy 
of type is nearly equally strong in the case of the Cape 
giraffe, despite the fact that as we proceed north a change 
in the nature of the markings is noticeable. The Baringo 
and Kilimanjaro giraffes, allowing for marked differences 
according to age and sex, are also known by a considerable 
number of specimens, so that there is every probability that 
their respective types of coloration are fairly constant, and 
the evidence for such constancy is still more satisfactory in 
the case of the Somali giraffe. As regards the other named 
forms, it must be admitted that their right to separation 
rests on the evidence of single specimens. Still, if con- 
stancy of type occurs in the other forms, the presumption 
is that it also obtains in these. 
If, of course, Kilimanjaro giraffes were met with among 
a Baringo herd, or vice versa, the case for the racial dis- 
tinctness of the local forms would be at once demolished, 
but no evidence of such an admixture of type has ever been 
recorded. Until this is observed, we are accordingly entitled 
—or rather compelled—to regard the differences in the colour 
and markings of giraffes from different localities as in- 
dicating local races precisely analogous to those of the 
bonte-quagga, or Burchell’s zebra. The extent of area 
covered by these local forms, whether some of them may be 
anything more than individual variation, and whether on 
the borders of their respective ranges they interbreed with 
the neighbouring races, or, as is more probable, keep 
perfectly distinct, are factors in the question still awaiting 
definite answers. 
In conclusion, reference may be made to the extremely 
important and valuable additions to our knowledge of these 
animals which have resulted from the specimens collected 
by Major Powell-Cotton during his recent expedition to 
East Central Africa. The only pity is that, by reason of 
the game-preservation laws, he was prevented from bring- 
ing away such a series of examples of the different local 
forms as would have sufficed to convince even the most 
sceptical of their respective constancy to a common type. 
Ree 
A DIRECTED SYNTHESIS OF AN 
ASYMMETRIC COMPOUND. 
Alt previous attempts to synthesise an optically active 
carbon compound have been based on one principle ; 
they have involved the combination of an inactive com- 
pound, containing an ethylene linkage or a carbonyl group, 
with an optically active substance to form an ester or gluco- | 
side, and the subsequent treatment of this product in such 
a way as to attach two different groups to a previously 
ethenoid carbon atom so as to render it asymmetrical. As 
Prof. Japp and others have pointed out, the two possible 
isomerides should not necessarily be formed in equal quanti- 
NO. 1791, VOL. 69] 
ties, so that on hydrolysing the new ester or glucoside one 
of the isomerides would preponderate, and therefore an 
optically active product should be obtained. Prof. Kipping: 
reduced the bornyl ester of benzoyl formic acid to the bornyl 
ester of mandelic acid, hoping to obtain an optically 
active mandelic acid. Prof. Fischer and M. D. Slimmer 
added hydrogen cyanide to helicin; they then hydrolysed 
the nitrile and subsequently the glucoside, with the object 
of preparing active oxymandelic acid. 
Prof. Kipping’s product proved to be inactive, and it was 
not conclusively established that that obtained by Fischer 
was active. 
In the last number of the Berichte, 
Prof. Marckwald, 
| of Berlin, describes the synthesis of active I-valerianic acid. 
Methylethylmalonic acid forms two acid salts, which in the 
case of the potassium salt are enantiomorphously related 
CO,K CO,K 
| [ees 
Et—C—Me Me—C—Et 
| | 
CO,H CO,IL 
whereas the two acid 
such as brucine, will 
Methylethylmalonic 
and will possess the same solubility, 
salts with an optically active base, 
in general have different solubilities. 
acid loses carbon dioxide when heated, forming methyl- 
ethylacetic acid, which contains an asymmetric carbon 
atom; it is to be supposed that from the acid brucine salts 
of the malonic acid the free carboxyl group will be pre- 
ferentially eliminated. Led by these considerations, Prof. 
Marckwald crystallised the less soluble brucine salt from 
the mixture of the two in the expectation of obtaining a 
material in which presumably the one form of the asym- 
metric compound would preponderate. This salt was heated 
at 170°. The valerianic acid obtained was optically active 
to the extent of —1°-7 per 10 c.c., which may be taken 
as an indication of the presence of 10 per cent. of 
l-valerianic acid. 
BAROMETRIC SEESAWS. 
ROF. HOFRATH JULIUS HANN has recently con- 
tributed an important paper to the Vienna Academy, 
an abstract of which is printed in the Akademischen 
Anzeiger, No. 1, of the Kaiserliche Akademie der Wissen- 
schaften in Wien. This paper is entitled ‘‘ Die Anomalien 
der Witterung auf Island in dem Leitraume 1851 bis 1900 
und deren Beziehungen zu den gleichzeitigen Witterungs- 
anomalien in Nordwest Europa.’’ In this Prof. Hann dis- 
cusses the relationship between the monthly and yearly 
means of the temperature, pressure and rainfall of 
Stykkisholm, in Iceland, for the longest time available, 
the temperature variations at Greenwich, Brussels and 
Vienna, the pressure and rainfall variations at Brussels and 
the pressure variations at Vienna. 
The results at which he has arrived are of very great 
interest, for they show that there is a most intimate con- 
nection between Icelandic meteorology and that of north- 
west Europe. For a full account of these the reader must 
refer to the abstract itself, but some of the results may be 
briefly summarised here. In the first place, for the three 
winter months the pressure variations of north-west and 
middle Europe are for the most part simultaneously of 
opposite sign to those at Stykkisholm, while the same re- 
versal occurs to a slight extent with the temperature and 
rainfall. Again, when the pressure variation for a month 
in Stykkisholm is negative, the probability for a positive 
temperature variation in north-east and Me Europe is 
0-82, and vice versd with a probability of 07 Again, 
contrasting temperature and pressure Se iaHoua, the follow- 
ing results were obtained :— 
Mean variation 
————————— Probability 
No. of Pressure Temp. of sign 
eases Stykekisholm pA Variation 
mm. aE 
Winter half year ... 67 +8°6 -1'5 o'8r 
Summer half year... 55 +3'8 —0'5 0°65 
Winter half year ... 72 —7°7 +14 0'90 
Summer half year... 50 —5'0 +0°7 0°76 
