SCIENTIFIC SUMMAIIY. 
421 
scarcely have deserved to he called the “ star of stars.” It is also too far 
from the ecliptic to he used conveniently as a regulator of the calendar. 
On the other hand, we must not he misled hy the name u messenger of 
light ” to suppose Dilgan identical with Venus, whose orh has been called 
Phosphorus and Lucifer (each name signifying the 11 light-bringer ”), for 
manifestly no planet could he used, as Dilgan was, to regulate a lunisolar 
calendar. We should he disposed to infer that the 11 star of stars ” was the 
Pleiades, if evidence can he found for the use of the Accadian word for 
.star to signify also a star-group (as astrum ). We have every reason to 
believe that the Pleiades were used to measure the year, and from the position 
of this star group near the ecliptic it would he far better suited than Capella 
for the purpose indicated in the above-quoted rule. 
Opposition of Mars. — Mr. N. E. Green, who did such good work in the 
observation of Mars at the last opposition, calls attention to the desirability 
of careful observations of the planet during October, November and Decem- 
ber next. This will be the most favourable opportunity for many years 
for examining the details of the equatorial continents. “ A careful search 
should be made for the remarkable dark canals figured by Professor 
Schiaparelli, which are represented by him as connected with the bays of 
the Sea of Maraldi and the Strait of Herschel, especially with the two 
points of Dawes’s Forked Bay. The northern declination of Mars will 
-compensate in great measure for the reduction in its diameter when com- 
pared with that of last opposition, and every use should be made of this 
occasion for the re-examination of previous drawings.” The astronomers 
of the Washington Observatory point out that the satellites can hardly be 
seen, even with the most powerful telescopes, except for a few weeks before 
and after opposition. It is to be hoped that those capable of taking part 
in the search for these minute and most difficult of telescopic objects will 
spare no efforts to obtain exact and trustworthy observations, whereby the 
theory of the Martian satellites may be advanced as far as possible. 
The Planets for the Next Quarter. — Saturn comes to opposition on 
October 5th, at 11 p.m. ; Neptune on November 3rd, at 10 a.m. ; and Mars 
on November 12th, at 8 p.m. On October 6th Mercury will be in superior 
conjunction with the sun ; Venus at her greatest brilliancy as a morning 
star on October 31st. 
Partial Eclipse of the Moon. — There will be a partial lunar eclipse, 
visible at Greenwich on the evening of December 28th ; first and last con- 
tacts of the shadow will occur at 3h. 37m. and 5h. 15m. respectively. 
The magnitude of the eclipse, lunar diameter as 1, will be only 0T67. 
BOTANY. 
Fertilization of Red Sea-iveeds by the Agency of Infusoria. — Professor 
Dodel-Port, of Zurich, has communicated to 11 Kosmos ” an account of 
some exceedingly interesting observations made by him on the fertilization 
of a Floridean Alga, Polysiphonia subulata, T.Ag., which appears from his 
researches to present a singular combination of analogies with the anemo- 
philous and entomophilous phanerogamous plants. An abstract of Professor 
