of the Fishery Board for Scotland. 



279 



materials for larval and early post-larval fishes, as well as the in veterb rates 

 on which they and the somewhat older stages feed. 



It is possible that certain of the forms mentioned above may pertain to 

 the same hydroid stock (representing perhaps younger and older stages, or 

 mere variations) ; but as our knowledge of the group, though largely 

 added to by the labours of Prof. Haeckel, is still in need of improvement, 

 it has been thought better to follow the descriptions of Forbes. It is also 

 noteworthy that the gonozoids of Corymorpha, which abounds off the 

 Budda Rock, have not yet been obtained. 



The true Medusse were represented by a single example of a young 

 Cyanea, § inch across the disk. It is remarkable that so few forms of 

 this group were secured. During ordinary seasons large examples are 

 abundant in June. 



The Ctenophores were numerous. The ubiquitous Pleurdbrachioe 

 continued throughout the month, and both large and small examples were 

 obtained. On the whole, the number of the large forms showed an 

 increase on the previous month, but this of course may have been as 

 much due to an immigration from the offing as to growth. The 

 larger forms were mature. One or two examples of Beroe, of moderate 

 dimensions, appeared only once, so that this species was comparatively 

 scarce. The most noteworthy example of the group was Besueuria 

 vitrea, M. Edwards, which occurred in numbers almost every day; and as 

 the month progressed a slight increase in size was apparent. Both young 

 and adult forms were common, the former ranging from inch or less 

 upwards. All the Ctenophores were captured in the mid-water net, 

 showing that they had frequented the deeper regions of the water. 



The Plutei of brittle and other stars and of Echinus were procured in 

 the bottom tow-net, and in the mid-water net on the 23d, but they 

 probably occurred even earlier. 



The surface-net captured a few specimens of Evadne Nordmanni 

 (Cladocera), a few Copepods, such as Halitemora longicornis, Ce?itropages 

 hamatus, and Acartia longiremis, along with a young Gammarus. More- 

 over, the Megalops-stage of Hyas also appeared towards the end of the 

 month, and a considerable number of zoese, probably of Carcinus and 

 Hyas, while a very young hermit crab inch long) occurred in the same 

 net. So firmly had it grasped a pelagic young Hyas that separation 

 could not be affected without the loss of both great claws. 



In the mid-water net were many Caligi, both 3 and 9 > some bearing 

 the parasitic Udonella caligorum, and with reproductive organs fully 

 devoloped. The 0#pm-stage of Cirripides also occurred. 



Amongst the higher crustaceans a few examples of the Megalops-stage 

 of Carcinus, and many long-spined zoese (Porcellana) were procured. 

 Young examples of Pandalus annulicornis, Hippolyte securifrons \ inch 

 each, and Montagua alderi were also noted. The exuvise of Cirripedes 

 were also not uncommon. 



Zoete and the Megalops-stages are often more abundant at the surface 

 in June along the eastern shores than they were this year. 



In the bottom tow-net, again, Copepods were far more numerous than 

 in either surface or mid-water nets, though the species did not vary, 

 stragglers from the dense ranks near the bottom having probably sought 

 the upper parts of the water. The species were Halitemora longicornis, 

 Acartia longiremis, and Centropages hamatus, as well as Qaligi on one 

 occasion. Swarms of Evadne Nordmanni frequented this part of the 

 water. The enormous numbers of this species must have an important 

 influence upon fish-food. The reproductive powers are remarkable. 

 Many examples of the (7^m-stage of Cirripedes are also present. 



