222 ANNULATA. 
NEPHROPS. 
SEGMENTS. APPENDAGES. NERVOUS SYSTEM. APERTURES. GILLS. 
u Ea 3 
Prostomium. Primary 3 a 5 
brain. e ele 
1 | Antennule. Brain. | Otocyst. 
d 2 | Antenna. Excretory pore. 
3+ 3 Mandible. - Mouth. 
|] 4 | 1st Maxilla. sg 
5|2nd uy a 5p as 
6 | ist Maxillipede Aas 
7 2nd " R 
4 8} 3rd u 8 t|2 
gJ 9 | Chela. Gangl. 1. 1|2 
= | 10 | 1st Leg. n 2 I/2/1 
& ] rr | and un nu 3. | 9 ap. r]2]/1 
12 3rd " in 4. 2 a ee” ae 6 
\ 13 4th "1 " 5. | 6 ap. I 
14 | 1st Swimmeret a 6: 
d 15 2nd tt tt 7. 
2] 16 | 3rd " " 8. 
84 17 | 4th " " 9. 
ae 18 5th " n IO. 
< 19 6th " }e t. 1 
e ost, gangl. IT. | anus. 
(Telson. ) 
II.—BLATTA. 
PHYLUM - ANNULATA (page 237). 
SuB-PHYLUM ARTHROPODA (page 240). 
Cass INSECTA (page 246). 
The common cockroach—Alatta ( Periplaneta Orientalis s) 
—is of a dark brown colour except when young and is 
usually about one inch in length. The American species 
(Blatta Americana) is considerably larger and is thus pre- 
ferable for dissection. 
The male cockroach is winged and the female has no. 
wings.” The cockroach is found most frequently in places 
with a high temperature, such as kitchens, 
laundries, or bake-houses, hence it is typically 
terrestrial. It is an omnivorous feeder and thrives in 
Habits. 
* Both sexes are winged in the case of B. Americana. 
