Cumacea: 15. Ekdiastylidae, 1. Ekdiastylis 135 



15. Fam. Ekdiastylidae 



1912 Ekdiastylidae, T. Stebbing iu: Ann. S. Afr. 3Ius., v. lOv p. 133, 146, 155. 



Telson large, with only 2 apical spiues. Antenna 1 with accessory 

 llagellum small. Antenna 2 of female with no elongate joint; flagellum of 

 male very long. Peraeopods 1 — 4 in male provided with exopods, but only 

 the first two pairs in the female. Only two pairs of pleopods in the male. 

 Endopod of uropods 2-jointed. 



1 genus. 



1. Gen. Ekdiastylis T. Stebbing 



1912 Ekdiastylis, T. Stebbing in: Ann. S. Afr, Mus., v. lOv p. 146, 155.] 



With the characters of the Family. The species E. insignis, E. argen- 

 tatus, E. ahhreviatus, E. fimhrtatus, appear te be in close alliance, with con- 

 siderable sexual differences. 



9 species. 



Synopsis of species : 



I Carapace strongly sculptured — 2. 



\ Carapace not strongly sculptured — 3. 



, Peraeopod 2 with 5tti joint scarcely as long as 6tli and 7th 



I combined IE. sciilptus 



i Peraeopod 2 with 5th joint much longer than 6th and 7th 



' combined 2. E. politua 



. Distal half of telson with fewer than 3 pairs of lateral 



I spines — 4. 



\ Distal half of telson with pairs of lateral spines not fewer 



' than 3 — 5. 



I Carapace with pair of infero-lateral processes near the front 3. E. insignis 



\ Carapace without such processes 4. E. mystacinus 



Carapace with 3 pairs of lateral processes 5. E. hexaceros 



Carapace with fewer than 3 pairs of lateral processes — 6. 



I Carapace with single pair of antero-lateral processes ... 6. E. argentatvxs 



\ Carapace without lateral processes — 7. 



j Carapace coarsely spinose 7. E. horridus 



^ Carapace not coarsely spinose — 8. 



J Telson of ? with 5 pairs of lateral spines 8. E. abbreviatus 



^ \ Telson of 9 with 3 pairs of lateral spines 9. E. fimbriatus 



1. E. seulptVLS (0. Sars) 1871 Diastylis sculpta, G. O. Sars in: Ofv. Ak. Forh., 

 u28 nr. 1 p. 71 | 1871 D. s., G. 0. Sars in: Svenska Ak. flandl., n. ser. v.9 nr. 13 p. 24 

 t. 1—9 f. 1—49 I 1873 D. s., S. I. Smith in: A. E. Verrill in: Kep. U. S. Fish. Comm., 

 V. 1 p. 554 I 1874 D. s., S. I. Smith & Harger in: Tr. Connect. Ac, ».3i p. 29 | 1879 

 D. sculptus, S. I. Smith in: Tr. Connect. Ac, v.5i p. Ill \ 1900 D. sculpta, Zimmer in: 

 Fauna arctica, v. 1 p. 425 | 1912 D. s.. Caiman in: P. U. S. Mus., vAl p. 605, 657 | 1912 

 Ekdiastylis sculptus, T. Stebbing in: Ann. S. Afr. Mus., ». lOv p. 146, 155. 



Pseudorostral lobes shortly produced in front of the prominent eyelobe, 

 horizontal, antero-lateral corners obtuse. Lower margin of carapace sinuous, 

 finely denticulate in front, hind margin carinate, frontal lobe crossed by 2 

 straight carinae, from the hinder a short median longitudinal carina passes to 

 join the foremost of 3 pairs of oblique curved lateral carinae by which the much 

 sculptured carapace is divided up into larger and smaller areas. The last 



5 



