1864. | Bates’s Naturalist on the Amazons. 181 
the great group of Insessores, Dr. Jerdon is certainly behind the age. 
It has long since been most satisfactorily demonstrated that the Te- 
nuirostres of Cuvier form a most ill-assorted group, which ought to be 
divided amongst the others in any natural arrangement, and that, ex- 
clusive of the Parrots, there are but three natural sub-groups of In- 
sessorial birds,—namely, the Fissirostres, Scansores, and typical Pas- 
seres. We might also object to Dr. Jerdon’s collocation of the Swifts 
and Swallows, to the situation he has assigned to Upupa, and to many 
other minor points. But on the other hand we must congratulate him 
on his giving the Megalemide their true rank as a distinct family, on 
his correct appreciation of the relation of the Hornbills, and on 
much that relates to his general arrangement of the smaller groups. 
On the other hand, Dr. Jerdon goes too fast in another direction, 
especially when it is recollected that his book is intended for learners 
and unscientific persons as well as for the initiated. The subdivision 
of the Genera is carried to by far too great an extent, and this, in our 
estimation, forms one of the principal defects of the book as a scien- 
tifie work. The best authorities of the day, in all departments of 
natural history, set their face against this indiscriminate multiplication 
of generic terms, which, as carried out by certain writers, bids fair to 
convert every species into a genus, and renders the burden of recol- 
lecting technical names almost insupportable. Generic differences 
ought to be founded on essential and easily recognizable points of 
structure. That this is not the plan followed in Dr. Jerdon’s book, 
every naturalist will very soon discover, and we fear the non-naturalists 
(if we may so express ourselves) will be sorely puzzled in their at- 
tempts to fathom many of Dr. Jerdon’s minute subdivisions of well- 
known groups. Who will recognize the Linnean Turdi under the 
names T'urdulus, Planesticus, and Geocichla? Who will appreciate the 
separation of the well-defined genus of Pipits (Anthus) into Pipastes 
Corydalla and Agrodroma? In thus following the phantasies of Kaup, 
and the mad vagaries of Bonaparte (in his latest writings), we can- 
not believe that Dr. Jerdon has acted well for his own reputation, 
nor wisely as regards the class of readers for whom his volumes are 
specially intended. 
NATURAL HISTORY ON THE AMAZONS.* ~ 
To no class of men are the thoughtful students of Natural History 
more deeply indebted than to those who, casting behind them all the 
,luxuries and pleasures ‘of civilized life, plunge into the forests and 
solitudes of far distant regions, there to hold communion with Nature 
face to face, and to obtain an insight into her workings and modes of 
action in situations which, under ordinary circumstances, would for 
* «The Naturalist on the River Amazons.’ By Henry Walter Bates. 2 vols., 
S8vo. London: John Murray, 1863. 
‘Contributions to an Insect Fauna of the Amazon Valley; Lrepmoprrra, Hel- 
eonide,” By Henry Walter Bates. (‘Linnzan Transactions,’ vol. xxiii. part 3, 
page 495.) 
