specimens of true Heliopeltas that he found in Cali- 

 fornia deposits. I have not found one in the same 

 material. Still more recently Mr. Christian informed 

 me that he has found the genus living. These I have 

 not seen. Mr. Gowan mentioned a double frustule 

 that came apart, that the number of rays differed in 

 the two parts. (I suppose by " double " he means a 

 whole frustule, both valves). Precisely the same thing 

 happened to a friend, who was mounting an 

 Aulacodiscus Orcganus, Bail. These instances prove 

 the worthlessness of the number of rays alone as 

 specific characters, as was specified by Bailey, thirty 

 years ago. — Charles Stodder, Boston, U.S.A. 



Standard Sizes for Eye-pieces.— In the 

 December number of Science-Gossip, p. 276, in an 

 American notice of "Practical Microscopy," by Mr. 

 G. E. Davis, the inconvenience of the want of a 

 universal gauge for eye-pieces and sub-stages is called 

 attention to. The Royal Microscopical Society have 

 certainly done their best to remove the difficulty. 

 After considerable trouble in ascertaining the amount 

 of variation in gauge, they recommend "that the 

 standards for eye-pieces should be two in number, 

 ■with a single standard for sub-stages. That the two 

 standard gauges for eye-pieces should be : for the 

 No. 1, 1 '35 inch, and for the No. 2, '92 inch, 

 (external diameter), and that the gauge for the sub- 

 stages should be 1 '5 inch (internal diameter). The 

 No. 1 gauge is generally used for the larger instru- 

 ments in England, whilst No. 2 is that adopted by 

 many Continental makers." This report , of the 

 committee appointed to investigate the subject was 

 presented to the Council, November 9, 1SS1, and 

 since published in the Transactions of the Society, 

 vol. ii. p. 595, 1882. By calling attention to the 

 subject in Science-Gossip you will greatly facilitate 

 the adoption cf these standard sizes. — IV. T. Suffolk, 

 F.R.M.S. 



" Studies in Microscopical Science." — It gives 

 us much pleasure to call attention to the following of 

 these " Studies " recently sent out weekly, and illus- 

 trated with slides, &c.': "Human Thyroid Body," 

 " Structure of the Sporocarp of Pilularia," " Thymus 

 Gland of Calf," " Thallus of Sticta pulmonacea," 

 " Human Pancreas," and " Thallus of Sticta aurata." 

 The list is so varied that every class of workers is 

 sure to be interested in these " Studies." 



The Guillemot. — From remarks in Mr. Ker- 

 mode's paper on the guillemot (in the number for 

 November) any one unacquainted with the habits of 

 the bird would imagine that it was unable to fly, and 

 had to climb from the water to its nest in the rocks. 

 But this is not the case, for it rises (when unhurt, as 

 the one described by Mr. Kermode must have been) 

 with ease from the water, and flies well, and with 

 great swiftness. — P. 



ZOOLOGY. 



A Work on the Butterflies of India, 

 Burmait, and Ceylon, by Major Marshall and M. 

 Lionel de Niceville, which promises to be a valuable 

 addition to entomology, is being issued in parts by 

 the Calcutta Central Press Co. I have seen Part I. 

 and perhaps the only objection to it, and that in a 

 beginner's eyes, is that it should have more coloured 

 plates. They would no doubt enhance its price, and 

 the descriptive letter-press appears to be sufficiently 

 full to aid any one in the identification of species ; but 

 where every spot and streak on a butterfly's wing is 

 important, coloured plates would be a welcome, as 

 well as a useful addition. — IV. J. S., Calcutta. 



Sphinx Pinastri. — The following notes relate 

 to some English specimens of this rare moth, taken 

 last summer : — Nine eggs hatched out August 7, and 

 took to Scotch pine freely. Two died at first casting 

 of skins — in two days. One egg added from the same 

 female — making eight altogether — of which two have 

 since died — leaving six. These have cast their skins 

 twice, and are now something like one inch long, and 

 feeding freely (August 20). August 23, 24. Larvae 

 have changed their skins for the third time. Sep- 

 tember 14. Larvae grown very much ; have now 

 changed six times. October 10. The last of the larvae 

 has now gone to earth. Unfortunately, September 15, 

 I was called away, and did not return in time to see 

 the last stage of the larvae. I have placed them in a 

 large glass vessel, with plenty of light soil and turf, 

 and have every hope they will emerge next July. 

 — F. H. 



The Great Grey Shrike (Lanius excubitor). — I 



had a fine specimen of this bird brought me by 

 Mr. J. A. Smith, of Akenham Rise Hall, near Ips- 

 wich, who shot on Saturday, December 2. Three 

 days afterwards, another specimen was shot in the 

 neighbourhood of the same town. — J. E. Taylor. 



The Black Stork in Ireland. — A very fine 

 specimen of the black stork [Ciconia nigra), was 

 shot last spring, near Killyleagh, on the shore of 

 Strangford Lough, in co. Down. It has been 

 preserved by the veteran taxidermist, Mr. Wm. 

 Darragh, at the Belfast Museum, and is now a valuable 

 object in the collection of R. Loyd Patterson, Esq. 

 Thompson (Nat. Hist. vol. ii. p. 178) says, that 

 this bird "is unknown as a visitant to the island." 

 Dr. Scouler included it in a ' Notice of Animals 

 which have disappeared from Ireland ' ( Journ. Geolog. 

 Soc. of Dublin, vol. i. p. 227), on the authority of 

 the following words from Giraldus : — ' Ciconiae vero 

 per totam insulam rarissimae sunt illae nigrae ' (Top. 

 Hib. 707). Four only of these birds have been re. 

 corded as obtained in England (Yarr. B. B. 2nd ed. 

 1845), none in Scotland ; the first in May, 1814 

 Although they migrate so far northward in summer 



