80 REPORT—1846. 
a superior kind of trout, which he thinks has not been described by naturalists: he 
calls it the “ Estuary Trout,” brackish waters being the locality it prefers. Its food 
differs from all others he has examined. Should it prove, on future inquiry, that the 
brackish water is the limit to its usual, or natural range, it may furnish a means of de- 
ciding on some difficult legal questions. As regards the celebrated questions raised 
by the Drumlanrig experiments, to which his first memoir gave, as he believes, the 
exciting cause, Dr. Knox thinks it not proved that the salmon smolt, that is the young 
salmon, ever remains longer in the river than a few weeks after rising from the gravel ; 
and thinks that the opinions founded on the Drumlanrig experiments are in this re- 
spect erroneous. 2nd. As regards the question of the parr, no new fact was added 
to its previous history by these experiments; the parr markings, which may be again 
made visible on scraping off the scales of the smolt, was a fact well-known to anglers; 
who at the close of the day found it difficult to say which were true parr and which 
salmon smolts. Mr.Scrope first gave a beautiful drawing of this fact. 3d. For at least 
a hundred years the opinion that the parr was the young of the salmon prevailed 
universally in Annandale. 4th. Willoughby had proved that the salmon-egg may be 
impregnated by the milt of the parr ; an experiment curious enough physiologically, 
but otherwise of no practical importance. 5th. Mr. Hogg and a great many others had 
marked the spring parr, and found that they returned to the rivers full-grown salmon. 
Thus no new fact was added to the natural history of the salmon by the Drumlanrig 
experiments. The author declined giving a decided opinion as to the real nature of 
the true parr; but, so far as his observations had yet gone, he believes that there is 
a fish which may be called the true parr, hitherto confounded with many other 
species having parr markings ; and that this true parr may ultimately prove a hybrid 
between the salmon or salmon trout and certain species of river trout. 
On the Application of the Method, discovered by the late Dr. Thibert, of Model- 
ling and Colouring after Nature all kinds of Fishes. By R. Knox, M.D. 
These models were shown. They consisted of the Vendace, the mackerel, the 
red-spotted trout of England, and the Lochmaben trout. This method of modelling 
will ultimately be preferred to all others; even to that in wax. 
On the Egg-purse and Embryo of a Species of Myliobatus. 
By J. Coucu, F.L.S. 
The author commenced by stating that the egg-purse was found in August 1845, 
in the refuse of a trawl-boat by Mr. Peach; and was obtained a few miles south of 
Fowey, in Cornwall. After mentioning how little is known of the egg-cases of the 
rays and sharks, he minutely described it ; and showed the difference between it and 
others, particularly dwelling on the structure of the surface, it being reticulated, 
whereas all the other ege-purses are smooth. In the egg-purse was a living young 
fish, which proves to belong to the genus Myliobatus of Cuvier, characterized by 
having the pectoral expansion separated from the head. These, from the direction 
of the wings, have been fancifully called sea-eagles. Ruysch, whose figures are for 
the most part copies from preceding authors without being improvements on the 
originals, but who, at plate 9. fig. 9, has given one tolerably characteristic, 
remarks that it has been called “‘ Sea Toad,”’ from the form of the head resembling 
that creature ; and the comparison seems appropriate, from the elevated head with 
a protuberant and lateral eye. The same author says that this fish is viviparous ; 
an assertion which the foregoing account shows to be incorrect. 
On the Crustacea found by Prof. E. Forbes and Mr. M*Andrew in their 
Cruises round the coast. By Prof. THomas Bett, F.R.S., PLS. ge. 
Having been requested by my friends Prof. Forbes and Mr. M‘Andrew to com- 
municate to the Section some observations on the contributions to carcinology made 
by those gentlemen in their recent cruises, I gladly comply with their wish; and 
although I have not to record many actual novelties in the species collected, yet 
