On the sponges collected during the 'Skeat expedition' to the Malay peninsula, 1899-1900 / by Igerna B.J. Sollas.

  • Sollas, Igerna Brünhilda Johnson.
Date:
1902
Catalogue details

Licence: In copyright

Credit: On the sponges collected during the 'Skeat expedition' to the Malay peninsula, 1899-1900 / by Igerna B.J. Sollas. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Sigmata 0*012-0’016 mm.; centrangulated sigmata 0’016 mm, Toxa : arms 0*025, 0*016; length 0*049 mm. Pulau Bidang. 10. Esperella sulevoidea, n. sp. (Plate XIY. figs. 8 & 9 and Plate XY. fig. 10.) Sponge creeping, attached at intervals, the attached parts forming thin disks. The skeleton consists of short stout fibres of styles rising from the surface of support and almost at once breaking up into 3 or 4 compact branches which run to the dermal membrane, through which they pass, their ends forming little hispid patches on the surface which are visible to the naked eye. The dermal mem- brane contains a network formed of compact multispicular fibres. In the meshes of ,this main framework lie the various forms of microscleres. The rosettes of anisochelie ai*e mostly confined to the superficial parts of the sponge. Spicules:— Tylostyles, with but slightly marked head, and with a peculiar undulating outline ; 0*360 x 0*012 and 0*360 x 0*006 mm. Sigmata 0*06-0*08 x 0*006 mm. Toxa 0*5-0*14 mm. Anisochelse in rosettes, 0*05-0*06 mm. Anisochelie scattered, 0*033 mm.; 0*012 mm. 11. Biemma democratica, n. sp. (Plate XY. fig. 9.) Sponge growing on a Lamellibranch shell and forming very thin encrusting sheets. The microscleres are in striking pre- dominance over the megascleres, which might almost pass un- noticed. The microscleres are sigmata of many sizes, ranging from 0*01 to 0*08 mm.; they are frequently fascicled, and in this case they may be either linear or, as is more commonly the case, they may be of the same thickness as solitary sigmata of the same length. The few megascleres are tylostyles often bent rather sharply just below the head, or sometimes with a second swelling immediately succeeding the head. Tylostyles 0*18x0*0025, head *005; 0*26x0*06, thickness of head *008 ; 0*56 x 0*006 mm., thickness of head 0*009 mm. Sigmata 0*08 x 0*003 mm. to 0*01 linear. I have included this species in the genus Biemma with some hesitation. Possibly it ought to form the type of a new genus. Pulau Bidang. 12. Desmacella fortis Topsent. Desmacella fortis Topsent, Revue Suisse de Zoologie, iv. 1896-7. With this species from the Red Sea and Bay of Amboina are identified two specimens differing somewhat in external features. Each is greyish in spirit, but has coloured the spirit in one case violet, in the other pink. The chief difference between the specimens is in the size and position of the oscula. In the violet-coloured specimen (which is [5]