400 
Fig. 
Tie. 16. 
7. Anacanthea nivea. X 1. 
Fig 20 
Vio, 24, 
26. 
26. 
Fig. 
bo bo 
Go. ST 
bo 
wo) 
MARIN® BIOLOGY OF THE SUDANESE RED SEA. 
PLATE 37. 
Esperella euplectellioides. X 3. 
Mywilla cratera, portion of surface. X 5. 
. Ophlitaspongia (?) digitiformis. X 3. 
Ophiitaspongia (2) digitiformis, skeleton arrangement. xX 20. 
; PLATE 38. 
Phakellia donnam. xX 9. 
Aplysina mollis. »X 4. 
. Portion of surface of Lymeniacidon caleifera. xX 4. 
PLATE 39. 
Phakellia palmata, X13. 
Phakellia palmata, skeleton arrangement. X 20. 
Ophlitaspongia (2) arbuscula. Xx 3. 
Portion of surtace of Huryspongia lactea. X 4. 
PLATE 40. 
Geodia micropunctata, skeleton arrangement. X 60. 
Ophlitaspongia (2) arbuscula, skeleton arrangement. x 609. 
Ophlitaspongia (?) horrida, skeleton arrangement. X 60. 
Prater 41. 
. Luryspongia lactea, skeleton. X 40. 
Euryspongia lactea, canal-system. X 200. 
. Duriella nigra, skeleton and canal-system. <x 40. 
LETTERING oN Puatss 40 & 41. 
ch., chone. inh.c., inhalant canal. 
cort. sk., skeleton of the cortex. - mes. f., fibres of the mesogloea. 
ex.c., eXhalant canal. pig., pigment-cells, 
fi.c., flagellated chambers. sk.f., skeletal fibres. 
