KNf)\VL|-.I)GK. 



JL'NK, 1912. 



antennae of nianv m^. .i^ >,iii lie clcarlv seen. 



The known s|)ecies fall into two families, the 

 representatives of one family, Acerentomidae {con- 

 taining most of the species), are without stigmata ; 

 those of the second family, Eosentomidae. possess a 

 complete tracheal system and two jjairs of stigmata 

 on the nieso- and metathorax respective)}'. All species 

 possess three pairs of abdominal appendaj^es. one on 

 each of the first three segments of the abdomen, but 

 in the .\cerentoniidae the second and tiiird pairs are 

 vestigial, whilst in the other family they are all 

 similarly well-developed and distinctlx' two- jointed. 

 Tiiese are the abdominal feet — ()edcs abdomiiiales- - 

 of Herlese. 



The Hrst family is composed of two genera. 

 Accrciitomon and Accrentuhis, the former being 

 characterized by the beak-like prolongation of the 



* My examples have been examined hv Silvestri, who 



u|)per lal)rum ; the second family contains but a. 

 single- genus, Eosenfoinon. Botli families (and the 

 three genera) are represented in my Ivnglish 

 material, but with the exception of a species of 

 Acerciitnmon, which I propose to name Acerentoiiwn 

 affinis on account of its close relationship to 

 Acerciitomoii doderoi Silvestri,* the type of the 

 order, and which occurs under the bark of an old 

 elm log in Gibside in considerable profusion and in 

 the Wear \'alley, my material is not well-preserved. 

 A minute new species of Eoseiitonioii occurs ver\- 

 sparingly in a t]uarry near m\- home at Penshaw, 

 County Durham, together with a recentlv-descrihed 

 Pauropod {Bracliypiiiiropus hibbocki Hagnalll. 



.\nyone familiar with the haunts of Paiiropiis will in 

 all probability become acfiuainted with the Profiira. 

 perhaps the most jirimitive and bizarre of insects. 



onsiders that they are not referable to his A. doderoi. 



SOL.-XR DlSTl'RB.A.XCES DURI.NCi .\l'l 

 P.v FRANK C. DENNETT. 



1912. 



During .Vpril only nine days — 7th, 19lh, 20th, and Z2nd to 

 27th — are reiiistercd as without solar disturbance. On twelve 

 others only taeniae were observed. The longitude of the 

 central meridian at noon on the 1st was 38° 11'. 



On the 2nd a pale faculic knot was seen at longitude S6°, 

 S. latitude 22°, and another near longitude 326° in high 

 southern latitude. Close to the eastern limb, latitude 11° to 

 13° South, a bright disturbance showed, which was better 

 seen on the 3rd and 4th when it contained a bright horseshoe- 

 shaped form. It was double, one from 287° to 293° and extend- 

 ing to 316°. These were not so well seen on the 5th and 6th, 

 when farther advanced upon the disc. On the latter date two 

 other faculae were visible arouiid longitude 261°. S. latitude 

 10°, and 48°, 19° S. On the yth a l<not was seen in S. latitude 

 near longitude 5°. On the 12th there was a pale faculic area 

 around longitude 183°, in 7° S. latitude. On the 14th a pale 

 facula was situated around longitude 297°, in 50° N. latitude. 

 On the 15th the faculae behind the spot group were visible 

 within the western limb. There appeared to be faculic 

 disturbance around longitude 202° in N. latitude 50° on the 

 16th. On the 17th, several small flecks of brightness were 

 noted scattered about the disc, but none were measured. On 

 the 18th, a pale faculic disturbance was situated near the 

 equator about longitude 108°. On the 21st there was a pale 

 facula near longitude 54°, N. latitude 3°. On the 28th, 29th 

 and 30th the faculic disturbance from 295° to 324°, in .S. 

 latitude 4° to 17° was within the eastern limb. 



No. 2. — A small pore about two days past the central 

 meridian on April 1st, and about which minute companions 

 showed at times. Its position, only seen on one day. is kindly 

 communicated by the Astronomer- Royal. 



No. 3. — When the faculic area, conspicuous within the 

 eastern limb early in the month, reached the middle of the 



disc, on the 8th, a line of pcnumbraless pores developed with 

 bright lips, over 42,000 miles in length, but very .soon new- 

 pores ahead increased the length to 82,000 miles. On the 

 9th there was a cmve of pores 112,000 miles in length. 

 During the day an ellipse of fourteen .spotlets opened within 

 the curve ; the outliers soon died out. The re.ir spotlet 

 increased to 15,000 miles in diameter by the 10th, and a 

 penumbral mass with at least four umbrae formed in front, 

 which for a little while was 21,000 miles in length. During 

 the 11th part of the middle of the group faded away, but it 

 was still a conspicuous object as it neared the western limb 

 on the 14th. The figure on the chart was that of April 9th. 



No. 4. — Was a spotlet with about three umbrae amid the 

 faculae within the eastern limb on 30th, other pores south and 

 west were seen on May 1st. On the 2nd a little group of 

 pores, 29,000 miles by 22,000 miles, was seen. There were 

 other changes noted on the 3rd, 4th, and 6th. but it was not 

 seen on the 5th, and on the 8th only a solitary pore was visible 

 apparently ju.st west of the place of the group, but it had gone 

 on the 9th. 



( )n the day of the Ivclipse there were no striking disturbances 

 on the disc, and the weather was all that could be desired. 

 There were some interesting prominences upon the limb, 

 which were first covered and then imco\ ered by the advancing 

 moon. Beyond the cusps of the crescent in the middle of the 

 eclipse the chromospheric lines stood out beautifully in the 

 spectrum. .About the same time three separate observers for a 

 short time thought the limar limb appeared projected upon the 

 corona, but each far.cied the appearance might be due to an 

 optical illusion. 



The chart is constructed from the combined observations of 

 Messrs. J. McHarg, A. A. Buss, E. E. Peacock, W, H. Izzard, 

 D. Booth, and the writer. 



