of certain Birds of Cuba. 19 
consequence of these vertebree being in birds always soldered 
together, and therefore very difficult to count. 
Number | Maximum num-| Minimum num-| Extent 
| of genera| ber of sacral ber of sacral of Observations. 
examined, | vertebra. vertebra. variation. 
1. Raprores. . 12 10 
Bubo. Buteo. 
2, INSESSORES . 13 8 
Corvus. Alcedo, 
8. RAsoREs . . 20 10 
Struthio, Meleagris, 
4, GRALLATORES 15 7 
Hemantopus, Fulica. 
e (The Petrel is not taken into 
SAGO ee 1b 10 consideration, as Cuvier 
Anas. Sterna. 
does not mention the num- 
ber of its sacral vertebrae. 
Here we see that the two Normal groups have the least number 
of sacral vertebre, and the three Aberrant the greatest. We see 
also that the number varies the least in the Raptores, and most 
in the Rasores. 
The fifth and last table that I shall offer relates to the ver- 
tebrz of the coccyx. 
Number | Maximum num-| Minimum num-| Extent 
Orders, of genera | ber of coccygian | ber of coccygian of Observations. 
examined, vertebra, vertebra. variation. 
1. Raprores. . 8 8 7 1 
Aquila, Aquila. Pandion, 
2. INsESsoRES . 22 9 6 3 
Hirundo, Loxia. 
8. RAsorEs . . 7 9 5 4 
Struthio. Meleagris. 
4. GRALLATORES 13 8 7 1 Hemantopus is not taken 
Gicanin Gia into consideration, because 
: ° Cuvier does not give its 
number of coceygian ver- 
5, Natatores.| 13 9 7 2 tebree. § 
Anser. 
p.2 On 
