286 MARGARET ROBINSON. 
Comparison with the Eye of Branchipus. 
As regards the shape of the pigment cells and the position 
of their nuclei and the arrangement of the nerve-end cells in 
three groups, this eye exactly resembles the median eye of 
Branchipus as described by Claus (‘ Wiener Arb.,’ vi, p. 59), 
but I cannot find any trace of a connective-tissue sheath like 
the one he describes as investing the eye. In his description 
he says nothing about a blood-space, nor does he mention any 
connection between the nerve-end cells and the ectoderm. 
This eye has been observed in adult specimens of the fol- 
lowing members of the Caridide : 
| Crangon fasciatus. 
Palemon squilla. | Pandalus annulicornis. 
Hippolyte Cranchii. | Pandalus brevirostris by Pro- 
Virbius varians. fessor Weldon, and in Palemo- 
Crangon vulgaris. netes varians by Dr. Paul Mayer. 
Palemon serratus. 
Before concluding, I must express my thanks to Professor 
Weldon for the assistance and advice he has most generously 
given me. 
EXPLANATION OF PLATE XIV, 
Illustrating Miss Robinson’s paper “On the Nauplius Eye 
persisting in some Decapods.” 
ec. Hctoderm. p. Pigment cells. x. c¢. Nerve-end cells. m. Muscle. 
g. br. Ganglion cells of brain. y.s. Punkt-substanz of brain. 4/. c. Blood- 
corpuscles. 4/.s. Blood-space. ch. Chitin. 7. ¢. Lateral eye. pig. corp. 
Pigment corpuscles in brain. comm. Circumcesophageal commissures. azt.1. 
First antenna. az¢.2. Second antenna. sg. Square of second antenna. 
r. Rostrum. c. ¢. Connective tissue. 
Fie. 1—Head of Hippolyte Cranchii with rostrum removed. 
Fic. 2.—Dissection of brain of Pandalus annulicornis. 
