MADEEPORARIA. 



PARTS I. AND II. 



By J. Stanley Gardiner, M.A., Felloiv of Gonville and CaiuK College, and 

 Demonstrator in Animal Morphology in the University of Cambridge. 



(With Plates LIX.— LXIV.) 



• J. INTRODUCTION WITH NOTES ON VARIATION. 



The present collection contains over 1,000 specimens of dried corals besides a large number 

 in spirit and formalin and a quantity of smaller pieces for comparative purposes. The reef 

 forms are mainly from the following localities: (a) Minikoi, the most southern bank of the 

 Laccadive Group ; (6) Goidu, the east island of Goifurfehendu atoll ; and (c) Hulule, the most 

 south-eastemly island of N. Male atoll. An attempt was made to collect as thoroughly as 

 possible — particularly at Minikoi and Hulule — for the comparison of the localities with one 

 another, and specimens were not generally taken from reefs elsewhere. In addition, dredgings 

 yielded a considerable number of specimens, although few hauls were taken on the outer 

 slopes of the reefs. 



The colours of the living colonies were noted at Minikoi, and both at Minikoi and Hulule 

 careful records were kept of the situations where the various species grew. In many cases 

 rough notes were added so as to show the actual positions in which the living corals stood, 

 both for comparison with the upheaved reefs of the locality and so far as possible to ascertain 

 how far mode of gi-owth is dependent on light and environmental conditions. These observations 

 were of immediate value in my studj- of the coral reef question, and have been of great assistance 

 in working out the collection. I had intended to have given an account of the variability due 

 to these causes, but the limited interest of the subject and the cost of suitable illustrations 

 have reluctantly compelled me to forgo the task. I have under each species indicated as 

 briefly as possible the variation that is found in the several colonies due to these causes. 



I divide the variation shown by corals into three classes : (a) that referred to above, 

 i.e. vegetative ; (6) continuoios ; and (c) discontinuous or specific. Of the latter the only instances 

 definitely known in corals, so far as I am aware, are those of Flabellum rubrum and stokesi 

 and of the two forms of Heterocyathus'. Below I have suggested certain additional 

 variations as belonging to this class, such as that shown by the two varieties of Acanthastraea 

 hirsuta, lobed and massive forms of Hydnophora microcona, and three similar species of 



1 Vide Marine Investigdiions in S. .4/rica, 1902, p. 211 et seq. and 1904 in the Press; also Pivc. Camb. Phil. Soc, 

 vol. XI. p. 463, 1902. 



G. II. 97 



