ARTHROPODA 
291 
may usually be distinguished by the developement of their 
olfactory hairs on the first antennae, by the absence of 
Se = 
Fic. 167.—Gammarus neglectus. 
I.-VI. Cephalothorax. 
VIL-XIII. Free thoracic segments. 
XIV.-XIX. The six abdominal segments, 
Anterior antennae. 
Posterior antennae. 
. Mandibles. 
Ist maxillae. 
2nd maxillae. 
. Maxillipede. 
. Thoracic limbs. 
. Three anterior abdominal limbs 
for swimming. 
MWA oF Cobh 
_ 
mn 
San 
a 
oostegites, and by the presence of 
the anterior thoracic feet. 
Female bearing eggs seen in profile. 
From Leuckart and Nitsche, after G. O. Sars. 
17-19. Three posterior abdominal limbs 
for jumping. 
20. Heart with six pairs of ostia. 
. Ovary. 
2. Hepatic diverticula. 
23. Posterior diverticula of the ali- 
mentary canal. 
. Median dorsal diverticulum. 
25. Alimentary canal. 
26, Nervous system. 
27. Ova in egg pouch, formed from 
lamellae on the coxae of the 
three anterior thoracic limbs. 
strong prehensile hooks on 
Appendages of Amphipods. 
1. Antennules. 6. 
2. Antennae. 
3. Mandibles. 
4. 1st maxillae. 17-19. 
ys PAL oe 
Maxillipedes (fused). 
7-13. Thoracic legs. 
14-16. Abdominal legs (turned forward). 
» », (turned backward). 
