250 
E. W. MACBRIDE. 
cellaria. p.ep. Posterior ciliated epaulette, p.o. Post-oral ciliated 
arm. pod. Unpaired tube-foot, pod. 1 Paired tube-feet. pr.o. Praeoral 
ciliated arm. r.a.c. Right anterior coelom, r.hy. Right hydrocele. 
sp. Adult spines, st. Stomodseum, i.e. larval month, v.ep. Ventral 
ciliated epaulette. 
Fig. 1. — An abnormal pluteus of Echinus miliaria viewed from 
the dorsal surface and magnified 110 diameters. Am., am 1 Left and 
right amniotic cavities, m.p. Madreporic pore. 
Fig. 2. — An abnormal pluteus of Echinus esculentus viewed from 
the ventral surface. Drawn from life by Mr. de Morgan and magnified 
110 diameters. Ech., ech. 1 The two “echinus-rudiments.” p.ep. The 
posterior ciliated epaulette characteristic of Echinus esculentus. 
st. Larval mouth. 
Fig. 3. — The same pluteus as that represented in fig. 2 at a later 
stage of development, viewed from the left side and magnified 110 
diameters, m. Adult mouth in the centre of Aristotle’s lantern, new. 
Nerve-ring. p.d. and p.o. Disappearing remnants of postero- dorsal and 
post-oral ciliated arms. sp. Adult spines. 
Fig. 4. — The same pluteus as that represented in fig. 3 at the same 
stage of development viewed from the right side ; magnification 110 
diameters. Ad. Adoral ciliated band shimmering through, m. Second 
adult mouth, new. Second adult nerve-ring. pod. Unpaired tube-foot 
pod. 1 Paired tube-feet. 
