On Dinophilus Gigas. 



By 



fV. F. R. i;Veldon, W.A., 



Fellow of St. John's College, Cambridge ; Lecturer on Invertebrate 

 Morphology to the University. 



With Plate XXVII. 



In the spring of last year Mr. Shipley brought to Cambridge 

 a few specimens of a Dinophilus, which he had found in 

 Mount's Bay, near Penzance. These he was kind enough to 

 place at my disposal ; and in April last I was able myself to 

 procure a larger number of specimens from the same locality. 



The animals were found in considerable numbers on red 

 seaweeds, &c., in pools, near spring-tide low water mark, on 

 the rocks to the west of St. Michael's Mount. The weeds were 

 placed in shallow white basins, with plenty of sea-water, for 

 from twelve to twenty-four hours, when the Dinophilus left the 

 weed, and were easily seen against the white wall of the vessel, 

 on the side turned towards the light. 



The length of the body varied greatly, the smallest specimens 

 found being about 0'75 mm., while the largest were nearly two 

 millimetres in length. The colour was a brilliant orange, uni- 

 formly distributed in granules through the skin, and more 

 intensely developed iu the stomach. 



The body consists of a head or prse-oral lobe, seven post- 

 oral segments, and a ventral unsegmented tail. 



The head is somewbat broader than the segment immediately 

 behind it ; its form is that of a truncated cone, and it is covered 



