ASCIDIAE SIMPLICES MOLGULIDAE 



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Fam. 4. Molgulidae. Solitary sessile Ascidians, sometimes 

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

 usually encrusted with sand, which is generally attached to 



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

 size). A, Ascidiella aspersa, 0. F. Muller ; B, dona 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 



A B 



FIG. 41. Branchial sacs of Molgulidae showing curved stigmata. A, Ascopera gigantea, 

 Herdman ; B, Molyula pyrifurmis, Herdmau ; C, Euyyra kergudenensis, Herd- 

 man. 



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 



