148 
On the Structure of the Bed Blood-corpuscles of 
nearly all the red blood-corpuscles of the tadpole. The corpuscles 
are oval, and the nucleus is very large. When the corpuscles were 
sideways, I could plainly see the nucleus projecting on both sides ; 
the nucleus does not project so boldly as in fishes, hut is bigger and 
longer. This accounts for the lanceolate or fusiform appearance 
when seen under a lower power. 
The tailing-off of the red corpuscle is due to the nucleus being 
displaced to the forward part of the envelope, as shown in the 
annexed woodcut, and this fact is submitted as one of the proofs of 
the heterogeneity of the living corpuscle ; in other words, that it is 
a compound body, and by no means simple and structureless. 
Fig. 1. — Tailing-off of the red corpuscle under a high power. 
„ 2. — Tailing-off' of the red corpuscle under a lower power. 
In the young newt I could also plainly see the nucleus in the 
corpuscles. They are similar to the frog-tadpole’s, but larger ; the 
nucleus is very large, and the marginal portion very thin. I have 
several times seen this portion double back over the nucleus. 
After the newt had been under the microscope some time, the 
circulation stopped in some of the small veins ; the corpuscles then 
looked circular, were not so transparent, and showed no trace of a 
nucleus. I would ask, may not this have been the appearance 
which was seen by Professor Savory, and which led him to the 
conclusion that the red blood-corpuscles have no nucleus ? 
In the living blood-corpuscles the nucleus has a very different 
