DEEP-WATER BIOLOGICAL PROVINCES OF THE INDO-PACIFIC 375 



phaenoides lophotes, C. wood-masoni, Coelorhynchus jlabellispinus, C. 

 quadricristatus, HymenocepJialus cavenosus, H. heterolepsis, Ventrifossa 

 petersoni, Lionurus polylepis, L. investigatoris, L. brevirostris, L. sent- 

 iquincunciatus and Mataeocephalus microstomus. 



Differing markedly from the Indian Ocean Province, the Indo-Aus- 

 tralian Province, which comprises the PhiHppines and the East Indies, 

 is characterized by comparatively cold water in intermediate depths. 

 Bordered to north and south by the warm Japanese and Australo-Pa- 

 cific Provinces, its cool deep temperatures are not duplicated in the 

 western Pacific between latitudes 35° north and south. This is in 

 strong contrast to the surface layers in which the w^armest water occurs 

 in the equatorial region. Another large group of endemic species— Ga- 

 domus denticulatus, G. introniger, Coryphaenoides hyostomus, Coelo- 

 rhynchus argentatus, C. maculatus, C. argus, C. amithi, C. radcliffi, C. 

 platorhynchus, C. commutabilis, C. tnacrorhynchus, Hymenocephalus 

 longiceps, H. nascens, Ventrifossa nigrodorsalis, V. divergens, V. nigro- 

 marginata and Trachonurus villosus—ra.nges throughout this area. 



The Indo-Australian Province may readily be subdivided. The Sulu 

 Sea, with its shallow sills and consequently very warm deep water, has 

 given rise to a few endemic species such as Coelorhynchus sexradiatus, 

 C. notatus and C. triocellatiis, and forms the Sulu Subprovince which 

 tends to isolate the Philippines from the East Indian region. Thus 

 limited to the Philippine Subprovince are Bathygadus sulcatus, Gado- 

 mus magnifilis, Coryphaenoides semiscaber, Coelorhynchus quincuncia- 

 tus, C. tho7npsoni, C. velifer, C. macrolepis, C. aciitirostris, Hyynenoce- 

 phalus longipes, Malacocephalus luzonensis, Ventrifossa macronemus and 

 V. lucifer, while Bathygadus filamentosus, Coryphaenoides tydemani, C. 

 aequatoris, Coelorhynchus acantholepis, Lionurus evides, L. vittatus, L. 

 parviceps and Mataeocephalus adjustus are known only from the East 

 Indian Subprovince. 



In addition to the very large number of endemic species in the Indo- 

 Australian Province, several more eurythermic forms such as Bathygadus 

 spongiocepSj B. jurvescens, Macrouroides injlaticeps, Malacocephalus 

 laevis and Lionurus pumiliceps range widely throughout both this area 

 and the Indian Ocean; others such as Gadomus multifilis, Coelorhynchus 

 parallelus, Cetonurus robustus, Hymenocephalus striatissimus and Tra- 

 chonurus villosus, range from the East Indies to southern Japan, while 

 two of them extend far into the Indian Ocean, and one of these is found 

 in northern New Zealand as well. The combined ranges of all of these 

 forms centering in the Indo-Australian Province indicate that this area 

 together with the Indian Ocean, the Japanese and the Australo-Pacific 

 Provinces constitute a single great unit which may be termed the Indo- 

 Pacific Superprovince. 



