230 Prof. W. King on the Tubulation of 
never witnessed the conduct of the animal during suction ; 
consequently he could not know anything from his own expe- 
rience concerning the organ which plays the principal part in 
that act. But he might have learned it from Swammerdam ; for 
it is precisely the pumping-ventricle, and not the cesophagus, 
which Swammerdam accurately describes*, comparing its move- 
ment to that of the balance in a watch, in the place alluded to by 
Burmeister. 
If, in conclusion, we now read Swammerdam’s treatise with a 
little attention, we shall find that his investigation, as far as it 
goes, is not less ingenious and faultless here than elsewhere in 
his incomparable work; nor is the description less full, perspicuous, 
and vivid, nor less rich in pointed expressions and happy compari- 
sons, written as it is in that naive and communicative style 
which even a whole century later was still characteristic of many 
excellent observers of natural history. Of course one ought not 
to content one’s self with the Latin translation, but study the 
Dutch original—an undertaking which at any rate to a Dane 
has no difficulty, and which he least of all could wish to evade. 
XXV.—On the Tubulation of the Valves of Rhynchopora 
Geinitziana, De Verneuil. By Professor W. Kine. 
In my former papers on Rhynchopora Geinitziana, I have described 
and inferred its histological character from surface-observations 
made with a Coddington lens+. But objections having been 
taken to a hand magnifier as possessing too low a power to settle 
unequivocally the question whether the above-named Permian 
fossil is, as I have all along maintained {, characterized by tubes 
passing completely through its valves, I have felt it necessary to 
* « Whenever the louse is busy sucking, we see a small current of blood 
just behind the sting (tab. 2. fig. 3 u), which shines through the head. 
Between and in front of the eyes, in the middle of the head, we perceive a 
tolerably large dilatation (2); so that the swallow, through the constantly 
ascending blood, in that place is appreciably distended. And then these 
parts contract themselves again so quickly that one scarcely sees any more 
blood. And this works so rapidly that one can hardly distinguish the ex- 
pansion from the contraction: so that I cannot compare it to anything 
better than to the quick movement of the balance im a watch. Behind 
the eyes in the head, we see nothing but a similar diminutive current of 
blood pass through; and this passage is, in my opinion, properly the 
gullet (f), which follows the swallow, and which is again dilated in the 
neck of the louse, as shown in the drawing (g). And allthis I have inten- 
tionally figured as a continued tube, in order that my description might be 
the clearer.””—Bzbl. Nat. 1. p. 79. 
+ Through a misunderstanding, I have hitherto called this magnifier a 
** Stanhope lens.” 
{ See Ann. & Mag. Nat. Hist. ser. 2. vol. xvii. p. 334, &., ser. 3. 
vol. xvi. p. 124, &c.; Reader, No. 138, August 19, 1865. 
