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Part III. — Seventh Annual M&port 



long chain, apparently from budding, after the manner of the species 

 described by I)r Murray in the ' Challenger' Report. 



The Ccelenterates continued in great profusion throughout the entire 

 month, at first solely occurring in the mid-water, and then subsequently 

 in the bottom-nets and at the surface. Moreover, they presented a con- 

 siderable increase in size, though small forms generally appeared with the 

 larger. The most conspicuous Hydromedusa3 perhaps were Thaumantias 

 melanops i T. henmjjhcerica, and an undetermined form of Thaumantias 

 (Plate V. figs. 6-9). T. melanops was frequently f of an inch in 

 diameter, and mature. While occurring almost daily in the mid-water 

 net, it also towards the end of the month was found in the bottom-nets, 

 though the specimens in these were small and immature. As in June, 

 T. Jwmisphc&riea was in great profusion in the mid-water net, and occa- 

 sionally appeared in the bottom-net ; and since the latter feature did not 

 occur previously, it may be presumed that it was not entirely due to the 

 capture of the medusoids on the way up. Larval anemones {Peachia), 

 now considerably larger, still abounded on this species and on the fore- 

 going (T. melanops), and they occupied diverse positions — now on the 

 outer surface or margin of the disk (Plate V. fig. 5), now on the 

 reproductive organs, and again on the inner surface of the disk, or perched 

 on the manubrium. T. hemisphcerica was likewise often in the fully ripe 

 condition, and some of the larger reached about j of an inch. An unde- 

 termined form (Plate V. figs. 6-9), possibly associated with T. yilosella, 

 often appeared in as great numbers, sometimes with the male organ fully 

 developed, but none were observed with ripe ovaries. They occasionally 

 reached If inch in diameter, and thus were notable from their size. 

 T. maculata at the commencement of the month was procured almost 

 ripe, and fully | an inch in diameter, and a week or two later others of 

 the same size fully ripe were captured. The variability in regard to 

 maturity was therefore as marked as in June — a condition probably due 

 to the growth or immigration of a new series. Other representatives of 

 this group were numerous minute medusa-buds, some probably pertaining 

 to Obelia, and which along with gonozoids of Stauridium, and apparently 

 Pudocoryne carnea, were generally procured in the bottom-nets. They 

 had perhaps only recently gained freedom, and along with the various 

 planulae frequented the lower regions of the water. Medusa-buds are 

 very common during July, not only in St Andrews Bay, but everywhere 

 round the coast. In certain parts the water is rendered luminous by 

 the minute medusa- buds of Obelia alone. These frequently occur near 

 the surface as well as throughout the water. Sarsia tubulosa, as in 

 the previous month, was small and immature at the commencement of 

 July, but attained a larger size as the month advanced — comparatively 

 few, however, were obtained at any given time. Moreover, while 

 Bougainvillia britannica was very abundant in June, appearing almost 

 daily in the tow-nets, it occurred very sjjaringly this month, a single 

 large immature specimen being captured on the 12th. 



Aurelta aurita amongst the true Medusaj was comparatively rare, a 

 condition so unusual in ordinary seasons. A young example, ^ an inch 

 across, was found in the mid-water net about the beginning of the month, 

 and a few larger in the same net on the 19th. 



In every haul of the mid-water and bottom-nets in J uly Pleurobrachia 

 occurred, both large and small examples at the beginning of the month 

 being present in the mid -water net, while in the bottom net the smaller 

 forms, larvae and eggs, were most abundant. At the same period large 

 forms (J inch in long diameter) seemed to have shed their ova. Towards 

 the middle of the month, larval forms and ova were frequent in the 



