ence. These have been very kindly compiled for me by my friend
and one time colleague Dr. Cecil Price Jones.

COMPARATIVE HAEMOCYTOLOGY OF LABORATORY ANIMALS.

--------------------------------------------------------------------
| Totals | Percentages
|------------------------------------------------------------
Animal | | | Hb, |Lympho-|Large |Poly- |Eosin-| Mast
|Red cells |White | per | cytes,|monos,|morph,| oph, |cells,
| | cells|cent.| per | per | per | per | per
| | | | cent. | cent.| cent.|cent. |cent.
--------------------------------------------------------------------
Frog | 490,000| 8,000| 58 | 40 | 10.0 | 22.0 |15 | 13
Mouse | 8,700,000| 8,000| 78 | 60 | 21.5 | 17.0 | 1.4 | 0.1
Rat | 9,000,000| 9,000| 85 | 54 | 7.0 | 37.5 | 1.3 | 0.2
Guinea-| | | | | | | |
pig | 5,700,000|10,000| 99 | 55 | 9.0 | 32.8 | 3.0 | 0.2
Rabbit | 6,000,000| 7,000| 70 | 50 | 2.0 | 46.0 | 0.6 | 1.4
Rhesus | 4,500,000|13,000| 77 | 43 | 5.0 | 50.0 | 1.3 | 0.7
Goat |14,600,000|15,000| 58 | 35 | 6.3 | 56.7 | 1.25 | 0.75
Fowl | 3,500,000|30,000| 100 | 49 | 3.0 | 42.0 | 1.0 | 5.0
Pigeon | 3,500,000|20,000| 101 | 43 | 9.0 | 43.0 | 3.0 | 2.0
--------------------------------------------------------------------
Man | | | | | | | |
(adult)| 5,000,000| 7,500| 100 | 25 | 5.5 | 65 | 4.0 | 0.5
Normal | (4.5-5) | (7-9)|(95- |(20-30)| (4-8)|(55- |(3-5) |(0.5-2)
limits.| millions.| thou-| 101)| | | 68) | |
| |sands.| | | | | |
--------------------------------------------------------------------

The above table represents in each case the average of a large number of
counts.

REMARKS.

_Frog._--The _red cells_ are large oval nucleated (20-25 mu by 12-15 mu)
discs, the nucleus relatively small and irregularly elongated or oval,
about 10 mu in length. Many primitive and developing forms are usually
observed--also free nuclei and many cells in various stages of
degeneration. Haemoglobin estimation is difficult owing to turbidity of
the blood after dilution with water. The _polymorphonuclear_ leucocytes
are large cells, about 20 mu; no definite granules can be observed. The
_eosinophile_ cells contain large deeply staining coc