THE EVIDENCE OF THE SKELETON I4I 
I have attempted in Fig. 53 to represent this close resemblance 
between the segmented branchial skeleton of Limulus and of Ammo- 
ceetes, a resemblance so close as to reach even to minute details, 
such as the thinning out of the cartilage in the subchordal bands and 
PROSOMA 
MESOSOMA 
Fic. 60.—DiaGRam oF AMMOCGTES CUT OPEN TO SHOW THE LaTwRAL SysteM oF 
CranraL Nerves V., VII., [X., X., AND THE BRANCHIAL CaRTILAGES. 
The branchial cartilages and sub-chordal ligaments are coloured blue, the branchie 
ted, gl., glandular substance surrounding the central nervous system and pass- 
ing into the auditory capsule with the auditory nerve (VIII). 
entapophysial ligaments respectively between the places where the 
branchial bars come off. 
In Fig. 59 I have shown the prosoma and mesosoma of Limulus, 
and indicated the nerves to the appendages together with the meso- 
somatic cartilaginous skeleton. 
In Fig. 60 I have drawn a corresponding picture of the prosomatic 
and mesosomatic region of Ammoccetes with the corresponding nerves 
