232 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1956 



longitude, the Greenwich meridian of Mars, passes through a dark 

 marking shaped like the open beak of a bird. To the left of this is a 

 large, dark and tapering marking, one of the most prominent of the 

 dark patches believed to be vegetation. This is called the Syrtis 

 Major. From its tip there runs a wide canal, Nilus, which curves 

 round to a dark dot known as Colos Palus. Another canal 

 Nepenthes, curves from the left side of Syrtis Major, passes a round 

 spot called Lacus Mceris and ends in another spot, Triton Lacus. 

 Although the Syrtis Major is always there, its shape varies from time 

 to time. Sometimes it has a long, pointed tip ; at other times, as in 

 1922, the tip is missing, while white patches have been seen hiding a 

 good deal of the Syrtis for a few weeks. These temporary white 

 patches are certainly clouds, and they are often seen over those parts 

 of Mars on which the sun is just rising, as though they form during 

 the night. The canals from Syrtis also vary a good deal in tint, while 

 Lacus Mceris, which on Lowell's theory would be a Martian city, is 

 sometimes small and faint while at others it is large and dark, pre- 

 sumably according to the amount of water available. 



The curved edge of Syrtis Major ends at a small round spot, Syrtis 

 Minor, about which is a dark streak called Mare Tyrrhenum. On 

 its left is another but larger patch, Mare Cimmerium, to which many 

 canals run. The area to the left of Syrtis Major and north of 

 Tyrrhenum and Cimmerium is desert, a sandy waste, in the center of 

 which is another round and dark spot, called Trivium Charontis. 

 This spot is peculiar because occasionally it becomes two separate 

 spots, which after a time reunite. If Trivium is a Martian city it is 

 situated in a very queer place, right in the middle of the desert. Two 

 canals, one called Styx and the other Hades, connect this desert spot 

 with other canals running up to the north pole, and the water appears 

 to travel along them all the way from the polar cap to Trivium in 12 

 degrees north latitude. 



Still farther to the left, or east, is another dark streak, Mare 

 Sirenum, on the opposite side of Mars to Syrtis Major, surrounded 

 by desert. East of this is a large light area, in the middle of which is 

 a dark patch from which canals radiate. This spot is sometimes called 

 the "Eye of Mars" because it looks just like an eye ; its proper name 

 is Lacus Solis, or the "Lake of the Sun." To the south of all these 

 dark areas is a large dusky spot, extending up to the snows around the 

 south pole and called Mare Australe, or the "Southern Sea." Here 

 and there are a kind of bright islands, such as Hellas and the Thyles. 

 Between the zero meridian and the Eye of Mars is a pointed dark 

 streak, the Margaritifer Sinus or "Pearl Bearing Gulf," and this 

 runs into the track of vegetation known as the Mare Erythrjeum. 



From these dark patches canals run across the northern deserts to 

 dark patches grouped around the north pole. Although there are few 



