CONVOLUTA KOSCOFFENSIS, GRAFF. 105 



Note on Convoluta roscoffensis Graff, 

 collected on the Natal Coast. 



By 



Ernest H^nrroii, D.Se.L.oii4l., 



Director of the Ntitnl Government Museum. 



With Plate XIII. 



At Scottsburg, on the Natal Coast, about forty miles south 

 of Durban, a Convoluta was discovered in September, 1904, 

 and in May, 1905. It is of a bright green colour and lives 

 in the sand. The animals crawl on the surface of the sand 

 grains, and also penetrate between the grains to a depth of a 

 quarter of an inch or more. They were found in the little pools 

 on the sand left by the tide, and occurred in such vast 

 nnniljers as to give the sand a bright green tint. The con- 

 voluta has only been found over a distance of a few hundred 

 yards. I have searched a considerable portion of the coast 

 both north and south of this spot, but the animal has not 

 been discovered elsewhere. 



I have carefully examined the species, and I have not 

 been able to separate it from C. roscoffensis. It possesses 

 the same longitudinal nerve-bands, two eyes, otocyst, and 

 the same disposition of the generative organs. The only 

 marked difference appears to be that the mouth is situated 

 further forwards than is described by v. Gi-aff in the typical 

 C. roscoffensis. The animal is capable of contracting its 

 body at the anterior end in such a manner as to form a 

 sucker-like depression or vestibule around the mouth. This 

 condition is especially noticeable wIkmi the animal has been 



