197 



of the branches truncate or disc-shaped, occasionally 

 somewhat rubbed. In the lower part the branches are 

 obtuse or truncate. 

 Fig. 2. The downwards turned part of a similar specimen, but 

 the ends of the branches most commonly obtuse. 

 3. The downwards turned part of a specimen that has been 

 much attacked by animals, with the branches rather 

 anastomosed and the ends obtuse, occasionally rounded, 

 and towards the sides truncate. The part that has 

 turned upwards is quite hollowed by boring-muscles, 

 leaving a peripherical portion about 1 — 2 cm. in thick- 

 ness, and rather rubbed by the influence of rapid tides. 



„ 4. The corresponding part of a specimen with the tip of the 

 branches errywhere obtuse or truncate. 



„ 5. The upper part of a specimen with the apex of most of 

 the branches forming disc-shaped and somewhat rubbed 

 expansions. The lower part is hollowed, much rubbed, 

 and the branches of the peripherical portion rather de- 

 nudated, often only the half or less of a branch left in 

 a longitudinal direction of the axis, but here and there 

 new local formations in development. 



„ 6. The lower part of a specimen, with wart-like processes 

 developed from the truncate or somewhat denudated 

 apex of some of the branches. 



Pl. 11. 



L. dehiscens f. typica. 



Habit-figure of an older and larger but fragmentary specimen, 

 the longest diameter about 32 cm., nearly cup-sbaped and rubbed 

 in the lower part. 



Pl. 12. 



L. dehiscens f. typica. 



Fig. 1. Habit-figure of a nearly spherical, j^ounger and somewhat 

 hollowed specimen, showing the part that has turned 



