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SUMMARY OF CURRENT RESEARCHES RELATING TO 
author experimented have a strong dislike for Glochidia as an article 
of food. Both adult and young are able to resist a certain amount of 
freezing. 
Molluscoida. 
a. Tunicata. 
Ecteinascidia and other Clavelinidse.* — Prof. W. A. Herdman gives 
an account of the characters and relations of this group of Tunicata, and 
criticizes the work done since he established the genus in his ‘ Challenger ’ 
report. He describes two new species, E. Thurstoni from the Gulf 
of Manaar, and E. Moorei from Alexandria Harbour. A classification of 
the Clavelinidse is proposed ; this family is of great interest phylogeneti- 
cally, because Clavelina comes nearer than any other known form to what 
we have good grounds for believing to be the common ancestors of all 
the simple or compound Ascidians (Proto-ascidiacea), and because this 
group occupies a central point between the simple and compound 
Ascidians; Bhopalsea links on in one direction to Ciona and the 
Ascidiidse, while Clavelina and Ecteinascidia pass in the other direction 
into Diazona , Chondrostachys , and the Distomidse. 
Tunicata of Plymouth-t — Mr. W. Garstang publishes the first part 
of a report on the Tunicata of Plymouth, in which he deals with the 
Clavelinidse, Perophoridse, and Diazonidae. Definitions of families, 
genera, and species are given, and there are copious synonymic lists. 
Pycnoclavella is a new genus for P. aurilucens sp. n„ in which the zooids 
are small and delicate, clavate, and arise by slender stalks from a more 
or less thick basilar mass of test-substance. 
£. Bryozoa- 
Budding in Bryozoa.i — Mr. C. B. Davenport has a preliminary 
notice of the results of his studies on budding in the Bryozoa. He 
makes some critical remarks on the recent work of Braem. It is 
stated that the polypides of the Bicellariidae, Membraniporidae, and 
Alcyonidiidae arise like those of Paludicella ; that is, from a mass of 
indifferent cells at the margin of the colony — a mass from which the 
body-wall is also derived. In all cases the polypide is formed by an 
invagination of the body- wall, which is two-layered at the margin of the 
colony. 
In marine Gymnolaemata budding seems to obey certain laws, which 
may be deduced from the study of erect colonies like Bugida ; these 
laws appear to be partly as follows ; — The lateral buds are formed 
earlier than and do not extend so far distally as the terminal buds. 
When a terminal and a lateral bud attached to the same proximal 
individual are each immediately followed by two buds, the two laterals 
lie adjacent, and the two terminal buds outside. Lateral buds tend to 
arise at the same time on two branches which spring from a common 
individual, but this may be modified. The marginal branches are the 
shortest and the middle ones the longest. There is one proximal 
individual to each “ fan ” ; this is followed by two and then by four ; 
* Trans. Liverpool Biol. Soc., v. (1891) pp. 141-63 (2 pis.). 
t Journ. Mar. Biol. Assoc., ii. (1891) pp. 47-67 (1 pi.). 
X Proc. Amer. Acad., 1891, pp. 278-82 (sep. copy). 
