MR. BOWMAN ON THE STRUCTURE AND USE OF 
72 
the Malpighian body to consist of the dilated extremity of the uriniferous tube, with 
a small mass of blood-vessels inserted into it. But in the several orders of animals, 
there are various modifications that merit notice. The most considerable of these 
regard the size of the Malpighian bodies, in connection with which are others in the 
mode of division of the arterial twig. The following Table exhibits this variety in 
their size, in a few species, and subjoined to each measurement, is that of the tube 
soon after its emergence. It will be seen that the tubes differ far less than the Mal- 
pighian bodies. 
Table of the Diameter of Malpighian Bodies, and of the Tubes emerging from them in 
Fractions of an English Inch. 
Diameter of Malpighian bodies. 
Diameter 
Maximum. 
Mean. 
Minimum. 
of tubes. 
Man 
1 
1 
1 
1 
T8 0 
1 
4 1 6 
1 
600 
1 
312 
1 
680 
1 
1000 
1 
4T6" 
1 
Badger 
1 
1 
1 
150 
1 
1 5 6 
1 
Dog 
1 
1 
Lion 
I 
1 35 
1 
80 
1 
200 
_JL_ 
2 60 
1 
130 
1 
Cat 
1 
90 
1 
Kitten 
1 5 6 
1 
25 0 
1 
Rat 
I 
5 1 2 
1 
Mouse ( Mus ) 
I 
220 
15 0 
1 
TT2 
Squirrel (Sciurns vulgaris) 
2 55 
1 
1 
7 70 
I 
Rabbit ( Lepus Cuniculus) 
2 0 7 
1 
Guinea Pig (Cobai/a) 
1 5 6 
1 
208 
I 
70 
1 
^ 50 
1 
6 2 5 
1 
600 
1 
Horse 
1 
5 5 
1 
Parrot ( Psittacus ) 
90 
l bn I 
Tortoise ( Testudo ) 
600 700 
1 
Boa 
J 
2J0 
2 4)0 
1 
1 
54)0 
1 
Frog ( Rana ) 
4-00 
1 
5 40 
Eel (Anquilla vulnaris ) 
25 0 
1 
20 7 
The kidney of the Boa shows very beautifully the reason of the different size of the 
Malpighian bodies in different parts of the same gland observed in all animals ; and 
also one cause of the striking difference in their size in different animals, and espe- 
cially in different-sized animals of the same natural group. Its lobes are much 
thinner at their convex border, opposite the hilus, than elsewhere. The tubes are 
consequently much shorter there, and I have remarked that the Malpighian tufts are 
also much smaller. This correspondence between the size of the Malpighian bodies 
and the length of the tubes, throws much light on the function of the former. A 
further study of the varieties here displayed in the size of the Malpighian tufts seems 
highly desirable. 
