ASCIDIAE SIMPLICES — MOLGULIDAE 



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Fam. 4. Molgulidae. — Solitary sessile Ascidians, sometimes 

 not fixed ; branchial aperture six-lobed, atrial fom--lobed. Test 

 usually encrusted with sand, which is generally attached to 



FlQ. 40. — Three simple Ascidians with vascular adhering processes from the test (nat. 

 size). A, Ascididla aspersa, 0. F. Miiller ; B, Ciona intestinalis, Linn. ; C, 

 Molgula oculata, Forb. 



branched hair-like processes from the test (Fig. 40, C). Branchial 

 sac longitudinally folded ; stigmata more or less curved, usually 

 arranged in spirals (Fig. 41); tentacles compound. The chief 



Pig. 41. Branchial sacs of Molgulidae showing curved stigmata. A, Aseopera giganlea, 



Herdman ; B, Molgula pyrifoniiis, Herdman ; C, Eugyra kerguelenensis, Herd- 



genera are — Molgula, Forbes (Fig. 40, C), with distinct folds in 

 the branchial sac (Fig. 41, B), and Eugyra, Aid. and Hanc, 

 with no distinct folds, but merely broad internal longitudinal 

 bars in the branchial sac (Fig. 41, C). In some of the Molgulidae 



