CATALOGUE OF TUNICATA. 97 



10 rows of stigmata, and from 3 to 5 stigmata in a mesh (fig. 9), but the 

 series next the endostyle on each side have 6 stigmata. 



The dorsal lamina is a plain straight membrane. 



The tentacles are of two sizes, 5 long and 5 short (fig. 10, tn.}. There 

 are about 16 small atrial tentacles. 



The dorsal tubercle has a circular aperture. 



The alimentary canal resembles that of the last species, and has the 

 same form of stomach. 



The reproductive organs consist of pear-shaped polycarps (fig. 11), 

 imbedded in the mantle. Some contain ova, and others spermatic 

 vesicles. 



Locality. Port Jackson. One specimen is about 10 cm. in length, 

 and one 15 cm. in length and about 7 cm. in breadth. 



This species resembles the last in appearance, but differs from it in 

 the tentacles (PI. Pst. I., fig. 10), which are only 10 in number. 



The colony, as a whole, is more opaque and browner in colour than 

 that of C. Sydney ens is, and the Ascidiozooids are less conspicuous. 



Chorizocormus leucophseus, Herdm., :;: PI. Pst. II., figs. 1 6. 



External appearance. The colony consists of elongated sub-cylin- 

 drical masses, united to form an irregular network (fig. 1), the whole 

 encrusting some brown Algae. Where the Ascidiozooids are few the 

 the colony is of a greyish yellow tint and transparent (the dark sea-weed 

 showing through), but where the Ascidiozooids are numerous the colony 

 is of a dark purplish and slatey hue. The largest colony measures 

 17 cm. long and 7 cm. broad. 



The test is full of large, conspicuous vessels with terminal knobs. 

 The blood corpuscles they contain, are not so dark-coloured as in the 

 preceding species. There are no bladder cells, and the test cells are few 

 and inconspicuous. 



The Ascidiozooids measure 2 to 2-5 mm. in length. 



The mantle has rather a regular musculature (fig. 2). Muscle bands 

 run longitudinally over the branchial sac, and are crossed by obliquely 

 directed fibres. 



Tlie branchial sac has 4 internal longitudinal bars on each side, but 

 no folds. There are 7 rows of stigmata, and generally 4 stigmata in a 

 mesh (fig. 3). In the series next the endostyle there are 6 to 8 stigmata. 

 The stigmata are regular and all of the same size. 



* "^Revision," p. 636. 



