108 
president’s ADDRESS SECTION D. 
Up to 1889 Saenger’s P. leuclcartii was the only recognised 
Australian species, and Hutton’s P. novw-zealandioe the onlv one from 
New Zealand. 
Most unfortunately for subsequent investigators, Saenger’s 
original description was published in Russian, in the Transactions 
of the Russian Assembly of Naturalists held at Moscow in 1867, so 
that few naturalists have the opportunity of seeing the memoir in 
question, and still fewer of understanding it. This is particularly 
unfortunate in view of the fact that a certain amount of doubt has of 
late years been thrown upon the question of the correct nomenclature 
of the Australian species, the facts of the case being as follows : — 
The common species in Queensland and New South Wales 
possesses fifteen pairs of claw-bearing legs, and an accessory tooth on 
the outer blade of the jaw. The colour of the skin is a mixture of 
indigo blue and dark-red in varying proportions; and it is undoubtedly 
viviparous. The last-named fact has been emphatically demonstrated 
by Mr. J. J. Fletcher in recent volumes of the Proceedings of the 
Linnean Society of New South Wales, and I have lately had the 
opportunity of confirming his observations in the case of specimens 
from New South Wales and Queensland collected and given to me by 
Mr. T. Steel, Professor Spencer, and Mr. I), le Souef. This species 
is universally accepted as P . leuclcartii. 
In Victoria, on the other hand, there are two species. The larger 
of these closely agrees with the northern form in size, general appear- 
ance, and anatomical structure ; but instead of being viviparous it lays 
eggs, which have beautifully and regularly sculptured shells, and from 
which the young animals may emerge after an interval of more than 
a year from the date of laying ! I believe that I have established 
these facts beyond dispute in my recent papers on the subject in the 
Proceedings of the Royal Society of Victoria aud of the Linnean 
Society of New South Wales. This Victorian species has, as a rule, a 
more or less distinct pattern on the dorsal surface, consisting of a 
series of segmentally arranged diamond-shaped patches in which the 
red colour is predominant, but in the darkest specimens these patches 
are represented ouiy by a row of small yellow or red spots on each side 
of the middle line. I had hoped that the presence of this pattern 
might serve as a means of distinction between the oviparous Victorian 
form and its viviparous congener in New South Wales. This hope was, 
however, destroyed by the dissection of a specimen collected by Mr. 
Steel at Blaekheath in New South Wales, which exhibited clear traces 
of the diamond-shaped pattern, and at the same time contained 
numerous advanced embryos in the uteri. The internal anatomy of 
the two forms also agrees very closely ; indeed I have not yet been 
able to detect any difference except in the appearance of the uteri r 
due to the presence of large, thick-shelled, regularly oval eggs, usually 
lying a little way apart from one another in the one ease, and of 
developing embryos with very thin membranes, and usually more 
crowded together, in the other. Although I have dissected Victorian 
specimens taken in December, May, and July, I have never found any 
embryos in them (as opposed to undeveloped eggs), while in New 
South W ales such specimens are nearly always present. So the larger 
Victorian species, so far as we know at present, differs only from the 
northern species in its oviparous habit. How this difference can be 
