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LOW 



their antennae, which are filiform 

 and cetaceous, and usually as long, 

 often longer, than the body of the 

 insect. 



LONGIP'ENNES. (from longus an&penna, 

 Lat. long wings.) A family of 

 birds in Cuvier's arrangement, in- 

 cluding those birds, which, from 

 the great strength of their wings, 

 whence they derive their name, 

 are to be met with in all latitudes : 

 the bill, in some genera is hooked 

 at the end, in others simply pointed. 



LONGIEO'STEES. (from longus and ros- 

 trum, a beak, or bill, Lat.) A 

 family of birds comprising the 

 waders, or birds with long bills. 



LO'NGITTTDE. (longitudo, Lat. longitude, 

 Fr. longitudine, It.) The distance 

 of any part of the earth to the east 

 or west of any place. The meridian 

 passing through the observatory at 

 Greenwich is assumed by the British 

 as a fixed origin, whence ter- 

 restrial longitudes are measured. 

 As each point on the surface of the 

 earth passes through 360, or a 

 complete circle, in twenty -four 

 hours, at the rate of 15 in a hour, 

 time becomes a representative of 

 angular motion. Hence, if the 

 eclipse of a satellite happens at 

 any place at eight o'clock in the 

 evening, and the nautical almanack 

 shows that the same phenomenon 

 will take place at Greenwich at 

 nine, the place of observation will 

 be 15 of west longitude. In the 

 case of stations differing only in 

 latitude, the same star comes to 

 the meridian at the same time, but 

 at different altitudes. In that of 

 stations differing only in longitude, 

 it comes to the meridian at the 

 same altitude, but at different times. 

 Supposing, then, that an observer 

 is in possession of any means by 

 which he can certainly ascertain 

 the time of a known star's transit 

 across his meridian, he knows his 

 longitude; or if he knows the 

 difference between its time of 



transit across his meridian and 

 across that of any other station, he 

 knows the difference of longitudes 

 between those two places. 



LOPHI'ODON. (from Xo0s and oSov?, 

 Gr.) A fossil genus of mammalia, 

 now entirely extinct, allied to the 

 tapir, rhinoceros, and hippopotamus, 

 and connected with the Anoplo- 

 therium, and Pala3otherium ; so 

 named from certain points, or 

 eminences, on the teeth. Although 

 this genus is not widely removed 

 from the tapirs, Cuvier thought it 

 desirable to separate it. Like the 

 tapirs the Lophiodon has six in- 

 cisors and two canines in each jaw. 



LOWEE CHALK. The chalk formation 

 or series is generally divided into 

 six distinct members, namely, the 

 lower green- sand ; the gault ; the 

 upper green -sand ; the chalk without 

 flints, or the lower chalk; the chalk 

 with flints, or the upper chalk, and 

 the Maestricht beds. This arrange- 

 ment is, however, altered by some 

 writers, inasmuch as a more minute 

 subdivision of some of the members 

 is concerned, depending on local 

 appearances. Generally speaking, 

 the lower chalk may be distinguished 

 from the upper by the absence of 

 flints, and by the superior hardness 

 of the chalk, which is sometimes 

 used for building-stone. The lower 

 is regularly stratified. In the north 

 of England, Professor Phillips 

 states, " The lower chalk is of a red 

 colour, and flints are found in it. 

 The only mineral found in the 

 lower chalk is sulphuret of iron. 

 The fossil remains are very numer- 

 ous aud all of them marine." 



LOWEE SILUEIAN ROCKS. In this di- 

 vision of the Silurian rocks, Sir E. 

 Murchison places the Caradoc sand- 

 stones and the Llandeilo flags ; these 

 are described under their particular 

 names. 



LOWEE NEW RED SANDSTONE. (The 

 Rothe-todte-liegende of the Ger- 

 mans ; the Gres des Yosges cou- 



