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MR JOHN EENNIE 



Proboscis Sheath and Nerve Ganglion. 



The proboscis or rostral sheath is double ; its retractor muscles at their terminations 

 upon the body-wall divide up into a number of spreading branches, between which run 

 numerous connecting fibrils (fig. 6). The nerve ganglion, which is spindle-shaped, is 

 situated at the base of the sheath. 



Egg-spheres and Embryos. 



The egg-spheres (Keimzellenballen, " swimming ovaries") are very numerous. Ova 

 of various sizes were observed, and shelled embryos were present in very large numbers 



-l--.-f.tt 



FIG. 1. E. strialus. 



in all the females examined. It seemed useless to measure the ova ; for although their 

 size is usually recorded as of value as a specific character, it was difficult to decide 

 whether the ova under observation at a given time were mature. I give, however, the 



following : 



Diameter of egg-sphere ..... '114mm. 



Length of unshelled ova (largest noted) . . -057 ,, 



Length of fully-coated embryos . . . '190 



Width of fully-coated embryos . . . . -04 



The embryos have a three-layered shell ; the outermost layer is thick and fibrillar, 

 the middle one has a constriction at each end marking off a rounded knob-like portion. 



(ROT. soc. OF EDIN. PROC., VOL. xxvi., PP. 440-441.) 



