TRANSACTIONS OP THE SECTIONS. 99 



On the Medusoid of a Tubularian Zoophyte, and its Return to' a fixed Cotxdition 

 after the Liberation of the Ova. By the Eev. Thomas Hincks, B.A. 



The author recorded in this paper observations which he had made on the repro- 

 ductive zooid of the Podocon/ne carnea, Sars. Specimens which he had kept for 

 some time exhibited the following changes. After a while the umbrella was thrown 

 back and turned inside out, occupying the position which it does permanently in the 

 free gonozooids of some of the Laomedece. It then collapsed and shriveUed up, 

 the remains of it hanging at the base of the peduncle, and the tentacles streaming- 

 out behind. The gonozooids (the so-called Medusse) had retui'ned to the polypite 

 condition. In this state they lived healthily for a time, the lobed mouth being tre- 

 quently moved about, as if in search of food. The ovaries were laden with eggs. 

 Similar observations had been made byDujardia and Peach, and by the author, in 

 the case of Coryne eximia. The changes subsequently ■«"itnessed had not been re- 

 corded hitherto. The peduncle became inactive, and, with the remains of the um- 

 brella, sloughed off, the ova probably being liberated at the same time. The ten- 

 tacles were then left, with their bulbous bases. The latter coalesced, forming a 

 hemispherical, orange-colom'ed mass supporting the arms, and around this mass an 

 ectodermal covering was developed. In this condition they continued for a while, 

 the tentacles being freely moved about. At length some of them became attached 

 by the base, and a thin nm of transparent matter formed round the edge of the disk. 

 The tentacles withered away, and hi one or two cases an ascending shoot sprouted 

 from the centre of the orange mass. Observations were not carried further ; but, 

 to all appearance, a polypite was in course of development. 



SenutrJcs on Stilifer, a Genus of quasi-Parasitic Molhislt:s,wit7i particulars of 

 the European Species, S. Tui'toni. By J. G^vrN Jeffreys, F.R.S. 



This paper was iUusti-ated by a diagi-am, representing a pair of Stilifers (male 

 and female) crawling among the spines of an -Ee/iJ/ww J);'o6ac/ii'e/«is, with magnified 

 drawings of the animal and its embryo. They had been carefidly examined alive, 

 and under favourable circumstances. S. Turtoni is exceedingly prolific. The whole 

 of its body is finely and closely ciliated, and the foot and mantle are constructed 

 so as to prevent the animal or its delicate shell being injured by the spines of the 

 sea-egg. The Stilifer was observed to feed not on the membrane or any other part 

 of the Echinoderm to which it attached itself, but apparently on its secretions, 

 having thus the scavenger habit of a dimg-beetle. It therefore could not be reck- 

 oned a true parasite. The history of the genus and a synopsis of all the known 

 species were given, as well as a detailed account of the animal of S, Turtoni. 



An Account of the Successfid Accomplishment of the Plan to transport Sahnon- 

 Ova to Australia. By T. Johnson. 



The preparations for the fourth attempt to transport from this country the ova 

 of the salmon were completed in January of the present year (1864). The plan 

 adopted upon this occasion diifered in detail from those of the previous expeditions, 

 being chiefly confined to depositing the ova amongst ice. Upwards of 103,000 ova, 

 obtained from fish taken out of English and Scotch rivers, were placed in small deal 

 boxes on beds of moss, and deposited in layers amongst the ice in the ice-house which 

 was built on board the ship ' Norfolk.' The expedition left this coimtry on the 

 21st of January, 1864, ani-sing out at Melbourne on the 16th of April. Several of 

 the boxes were opened, and the ova appeared in most cases in an excellent condi- 

 tion. The ova in the boxes near the bottom of the ice-house were not so healthy. 

 By the 20th of April the whole of the boxes, excepting those detained at Melbourne, 

 were safely deposited in the breeding-boxes on the River Plenty, Tasmania. The 

 analysis of the boxes showed that, out of 103,000 ova sent out, some 31,000 only 

 were deposited. On the 4th of May the fish began hatching out : and by the Oth 

 of June the whole, together with the few trout-ova, had thi-own aside the shell 

 and were dissporting in their native element. The total number of fish up to the 

 latest advices was nimibered at between 3000 and 4000. Several reasons have 

 been given as the causes of the great loss of ova, as also the probable results of the 



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