MOLGULA CITKINA. 65 



situated immediately below the reproductive organ ; 

 it is large, not much bent, and rounded at the ends. 



This species differs from all the others of the genus 

 yet observed in not being clothed with extraneous sub- 

 stances, owing to the absence of glandular fibrils ; it is 

 also the only species except If. complanata which is 

 firmly attached by its base [or side]. The external 

 character afforded by the number of segments in the 

 apertures, however, is well borne out by the internal ; 

 the tentacular filaments and characteristic branchiae 

 showing it to be a true Molyula. 



The large ovate male casca are also very peculiar, 

 and in their form have much the appearance of the 

 same organs in Glavclina lepadiformis . 



Genus 5. EUGYRA Alder & Hancock, 1870. 



[Molgula (pars) FORBES in Brit, Moll. I (1848), p. 36.] 

 Euyyra ALDER & HANCOCK [in Ann. Nat. Hist. (4) VI 

 (1870), p. 367]. 



Body globular, unattached, covered with glandular 

 fibrils, and a coating, more or less complete, of fine 

 sand. Test usually thin and transparent, fibrillous. 

 Branchial aperture 6-lobed, atrial 4-lobed ; placed on 

 slight tubes, nearly inconspicuous when contracted. 

 Tentacular filaments branched. Branchial sac without 

 folds, but with longitudinal plates or bands, the meshes 

 or secondary vessels regularly convoluted, each being 

 composed of a double spiral coil meeting at the apex 

 and produced into a little cone. Reproductive organs 

 on the right side only, placed partially within the lower 

 loop of the intestine and partially above it. 



Eugyra is extremely like Molgula in external appear- 

 ance, but differs nevertheless so greatly i n internal 

 structure, that were it retained in that genus, the 

 characters of the latter would have to be defined much 

 more loosely than seems either proper or convenient. 

 Besides being distinguished by many minor points, 



ii. 5 



