. 
Geology and Natural History. 889 
son. Anda oe he mentions the occurrence of the Moni and 
Be cose in Lakes Superior and Michigan, and alludes to the 
giving the results of Mr. Smith’s qesbarthes had been sent to him, 
before he undertook his dredging operations, by Mr. Smith, at 
his request, so that he could not have been ignorant of them. 
Some suitable acknowledgement of the labors of Mr. Smith i 
dredging so extensively, and so promptly publishing the ~— 
of his researches, was in justice demanded of Mr. Nicholson, w 
has evidently derived some benefit from them. Not to cae 
is name at all in this connection was a kind of erebenad which, 
fortunately, is rare among American naturalists of repute 
te ae 6 
1. Tieghem on the Cotyledon of Graminec, etc.—The old con- 
troversy between Richard and Mirbel, early in the century, 
ta a ag structure of the embryo in grasses, was never 
ttled. Reduced to modern morphological terms, the views 
Gaieteied amount to three. According to the first, the seutellum 
or outermost piece of this complex embryo is the cotyledon, the 
lobule agete (which is not always present) represents the second 
leaf, the pileolus, or conical tunic which envelops the parts of 
the’ plumule that develop into eer gh is the third leaf, so that 
the earliest green leaf is the fourt the series. Under the 
Second view, the scutellum is also the edt ylodeil, but the opposing 
* A brief account of the first dredging expedition (1870) in L. Michigan, has 
been published j in the Trans. of the Wisconsin oes y of Science, ete., 1872, 
P. 98, by Dr. yy, who was one of the 0 r of 
the Mysis and other eep-water species found in the sto: 
( is paper has been reprinted in the Annals and Magazine of N: 
Hist., April, 187 p- 319. Another exploration was carried on in 1871, but the 
collections of both these expeditions were burned in the 
vl tacea from the former was, however, given to Mr. 8. I. Smith, just — 
the fire, by Dr. Stimpson, with his MSS. names attached. ese names 
given only provisionally, and without much examination, and should not have 
been — we but as poem 4 ee appeared in Dr. Hoy’s paper and its albino int, it 
Il for me to state h re, on the authority of Mr. Sith who has compared 
the original specimens t msg rc ha brevistilus Stimp. M paeee See 
and Mysis diluvianus See penis Gis ono on tyene alias Lo 
Am. Jour. ape foresees Vou. V, No. 29.—May, “a 
