NATURE 
333 
THURSDAY, AUGUST 12 
rat} 
1886 
CENTRAL AMERICAN ENTOMOLOGY 
Liologia Centrali-Americana. Insecta: Coleoptera. Vol. 
III. Part 2, “ Malacodermata,” by the Rev. Henry 
Stephen Gorham, F.Z.S., &c. (1880-86.) Vol. V. 
“Longicornia,” by Henry Walter Bates, F.R.S. 
“ Bruchides,” by David Sharp, M.B. 
Porter, 1879-86.) 
“Y¥*WO more instalments of the entomological portion 
of this great work show how earnestly it is being 
pushed on; and if it can be completed on the same 
lavish scale of illustration, and with the same thorough- 
ness of execution, it will afford materials for a true con- 
ception of the richness of insect life in the tropical regions 
far beyond anything that has been hitherto attempted. 
Not only-will it be superior to any other work of a similar 
character, but it will probably surpass in magnitude all 
the other works dealing with tropical insect-faunas com- 
bined. 
The plan and method of treatment being exactly the 
same as that of Mr. Bates’s volume on the Cicindelide 
and Carabide, already reviewed in NATURE (vol. xxxiii. 
p- 77), it will only be needful here to make a few remarks 
on points of general interest. Taking first the Malaco- 
dermata—a group represented in Britain by our Telephori, 
“soldiers and sailors,” our glow-worm, and other allied 
forms—Mr. Gorham informs us that nearly one-fourth of 
all the known species of the world are here described 
from Central America, a preponderance in this district 
which is due no doubt to the fact that the group has 
never been a favourite one among coleopterists, and has 
thus been comparatively little attended to by collectors in 
the tropics. The large number of 813 species here 
enumerated as against 1272 of the favourite Longicornes, 
shows that it is not impossible that this tribe may one 
day rank among the richest groups of beetles. From a 
comparison of certain of the best known families in dif- 
ferent parts of the world Mr. Gorham is of opinion that 
the total number of species in the tribe is not less than 
12,000. He also states that the tropical American forms 
are as a whole very distinct from those of Africa and the 
Eastern tropics, and that they rank as “ persistent forms 
of an earlier stage of development.” This is specially 
interesting, because it agrees so well with the fact that 
nowhere else in the world do low forms of mammalia and 
birds constitute so large a proportion of a wonderfully rich 
fauna as in tropical America. Another suggestive remark 
is, that whenever “a genus is common to Central or 
South America and other distant parts of the world, it is 
also the case that it is represented by a species also iden- 
tical or nearly so in both districts.” Many examples are 
given of this interesting fact, and the no doubt correct 
solution is suggested, that in these cases there must have 
been a comparatively recent transmissal, either from one 
country to another, or from some common centre to both. 
The Miocene beetles of Switzerland exhibit so close a 
resemblance to living forms that we may well suppose 
these identical species to have been common to Europe 
and North America in Miocene times, and to have passed 
southward to the Old and New World tropics respectively 
when the temperate zones became unsuitable to them. 
VOL. XXXIV.—No. 876 
(London: R. H. 
Of Longicornia about 9000 species are known, so that 
those from Central America alone are nearly one-seventh 
of the whole; but in this tribe more perhaps than any 
other is our knowledge imperfect, owing to the bulk of 
the species being restricted to the virgin forests, where 
they are very local and marvellously specialised ; while 
though exceedingly abundant under favourable conditions 
—that is, when extensive clearances in the forest have 
been recently made—yet at other times they are so scarce 
that it is impossible to obtain even a moderate collection 
of them. 
Mr. Bates remarks on the wonderful “endemicity ” of 
the tropical American Longicorn fauna, 304 genera out 
of 330 being exclusively American; while both he and 
Mr. Gorham insist on the whole of the Central American 
fauna, including that of the highlands of Mexico, having 
tropical rather than north-temperate affinities. As 
regards the Malacodermata, however, the northern parts 
of Mexico are said to be “ totally unexplored,” while Mr. 
Bates states that there are 30 northern generic forms 
which reach Mexico but rarely go further south. 
The Bruchides form a small tribe of usually minute 
beetles which have been so imperfectly collected in 
the tropics that no comparisons of any value can be 
made. No less than 150 species are here enumerated, 
forming nearly one-fourth of all that are yet known, and 
nearly 120 of these are new species, 25 of which are 
figured. 
On looking over the beautifully executed coloured 
plates, on which nearly 500 new species of Longicornes 
are figured, we are struck by the great preponderance of 
protective tints in these insects, whole plates being filled 
with species of delicately mottled brown or grey colours 
evidently harmonising with the varying hues and rugosi- 
ties of the tree trunks on which they rest ; while those of 
more elegant forms and brilliant tints are usually of 
smaller size, except when they gain protection by their 
resemblance to other inedible insects. It fortunately 
happens that the other group treated in these volumes— 
the Malacodermata—are very largely, if not wholly, such 
a protected group, it having been found by experiment 
that birds will not eat our gay-coloured Telephori, and 
Mr. Belt found the same to be the case with the fire-flies 
of Nicaragua and their allies. In all parts of the world 
these insects are mimicked by others which have no such 
protection, and it is interesting to compare the plates in 
these two volumes and to see how many of the Longi- 
cornes have taken on the form and colouring of the Mala- 
coderms. Whenever I noticed a pair which undoubtedly 
resembled each other, I turned to the descriptions, and in 
every case found that they inhabited the very same 
locality. Thus the Longicorn O¢heotethus melanurus 
imitates the Malacoderm Lucidota discolor, both found at 
Chontales, the species mimicked having however, as is 
usual, a wider range. TZethlimmena aliena and Lygisto- 
pterus amabilis, another mimicking pair, are both re- 
corded from Chontales only. Cada albicornis, from 
Panama, resembles two species of Malacoderms, Sz/zs 
chalybeipennis and Colyphus signaticollis, both from 
Panama, and both taken on the Volcano de Chiriqui. If 
these last two are both inedible, it is a case among the 
Coleoptera similar to the numerous interesting cases of 
protected genera of Heliconoid butterflies resembling 
Co) 
