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the transverse and internal longitudinal bars. In this network lie 
the delicate, coiled interstigmatic vessels. 
Dorsal lamina short, quite plain ; no ribs nor teeth. 
Tentacles large and branched, dark green, ten in number, with a 
few additional very small intermediate ones. 
Olfactory tubercle prominent, both horns much coiled, forming 
large spirals. 
Two specimens from Station 315 (Falkland Islands); 5 to 12 
fathoms. 
Molgula forbesi, n. sp. 
External appearance .- — Shape globular, slightly elongated dorso- 
ventrally, not compressed laterally ; posterior end regularly rounded ; 
edges convex; anterior end slightly projecting and flattened, not 
attached. Apertures both at anterior end, not distant ; atrial rather 
more prominent than branchial, both slightly projecting, branchial 
pointing ventrally. Surface entirely covered with a close coating 
of sand grains. Colour dull brown. Length, 1 # 8 cm. ; breadth, 2 cm. 
Test not thick, but stiff ; quite opaque. 
Mantle thin, transparent, viscera seen through distinctly ; muscle 
bands numerous, but very fine. 
Branchial sac with seven folds on each side. Internal longi- 
tudinal bars strong, three or four on each fold. Stigmata very 
irregular — being straight, and arranged in transverse rows in some 
places, while in others they are curved and arranged in spirals or 
irregularly. Transverse vessels varying greatly in size and position, 
often quite irregular. Delicate horizontal membranes frequently 
present between the folds. 
Dorsal lamina , a short and narrow membrane, with a plain edge. 
Tentacles compound, about twelve large and twelve small placed 
alternately. 
Olfactory tubercle simple, placed at the posterior end of a deep 
and irregular peritubercular area. The left side extending further 
forwards than the right ; both horns turned to the left. 
One specimen from Port Jackson, Australia; 2 to 10 fathoms 
Molgula pyriformis, n. sp. 
External appearance. — Shape pyriform, almost triangular; anterior 
end wide, truncated ;■ posterior narrow, pointed ; both edges convex. 
