496 Miscellaimuus. 



devoted himself with great assiduity to the study of the anatomy 

 and physiology of this interesting class of the Molluscoida, and, 

 when compelled by increasing weakness to relinquish the use of 

 the microscope, had nearly, if not quite, completed his investigation 

 of the Ascidiadaj. Both manuscript and plates of this work are, we 

 arc led to hope, in such an advanced state that there is still u 

 prospect of the work being published. During the last three years, 

 when unable from ill-health to pursue his microscopic dissections of 

 the Tunicata, he turned his attention to the investigation and de- 

 scription of the fossils of the Coal-measures ; and to this we owe 

 the valuable series of papers published by him, in conjunction with 

 Mr. Atthey and Mr. Howse, on some of the rarer specimens in the 

 remarkably fine collection of the former of these two geologists. 

 In 1858 the Eoyal Society awarded Mr. Hancock the Hoyal Medal, 

 in recognition of his scientific labours in general, and with especial 

 reference to his exhaustive paper " On the Organization of the 

 Erachiopoda " (Phil. Trans. 1858, p. 791). He was a Fellow of 

 the Linuean Society, and also a Corresponding Member of the 

 Zoological Society. In 1866 the Imperial Royal Botanical and 

 Zoological Society of Vienna conferred upon him and upon his friend 

 Mr. Alder the diploma of Honorary Fellow. In the list of scientific 

 papers published by the Royal Society there are thirty-one papers 

 pnblished in his own name, in conjunction with Mr. Alder sixteen, 

 with Dr. Embleton five, and with Mr. Norman one ; and he has 

 published several papers in the 'Annals' and other works since 

 this list was printed. His papers on the fossils of the Carboniferous 

 strata consist of twelve written in conjunction with Mr. Atthey, and 

 four with Mr. Howse. — J. E. Gray. 



Oil a Variety of Chersina angulata. 

 By Dr. J. E. Gray, F.R.S. &c. 



The British Museum has just received an adult male specimen of this 

 tortoise, which was formerly in the possession of Mr. Arthur Adams, 

 who obtained it at the Cape of Good Hope. It is peculiar for having 

 the hinder marginal plate on the side of the caudal plate shorter than 

 iisual, so that the suture between it and the plate before it is on the 

 same line as the suture between the hinder edge of the fourth costal 

 plate and the lateral edge of the fifth vertebral plate. I am inclined 

 to regard this as an accidental variation ; for in another large speci- 

 men of the same sex in the same collection, and in ten other specimens 

 in the British Museum, the suture between the hinder and penulti- 

 mate marginal shields is always before the suture between the hinder 

 costal and last vertebral shield ; but I do not believe that this differ- 

 ence is specific as one zoologist seemed inclined to consider it, because 

 the width of the last marginal plate varies in different specimens, 

 and in one specimen they dift'er on the two sides. I therefore 

 only regard it as an accidental variety, which also has the upper 

 maigin of the caudal plate much narrower than usual ; but the shape 

 of this plate varies in the male specimens in the Museum. 



