ANATOMY OF THE OPHIDIA. 419 



and in the Colnbroidea the organ is bilobate and the walls have 

 deep longitudinal grooves. Tliis form more closely resembles the 

 latter. 



Cyclocorus lineatus Reinhardt. 



Specimen. No. 15240. California Acad. Sci, Olongapo, 

 Luzon, P.I. Female ; total length 503, tail 81 mm. 



Squamatiou. — Scale-rows 17 anteriorly ; the V row suppressed 

 at the 127th gastrostege on the riglit and the 125tli on the left, 

 leaving 15 rows which are continuous to the vent. The last 

 scale in the row that is dropped is before an enlarged scale 

 in the row below. Anteriorly an oblique series of scales 

 starting at one gastrostege terminates at the tenth to the rear. 

 Gastrosteges 163. Anal entire. Urosteges 41, single, Prte- 

 oculars 2, postoculars 2. Anterior temporals 2, posterior 2. 

 Supralabials 8 ; the third to the fifth entering the eye. Infra- 

 labials 9 ; the first to the fifth in contact with the anterior 

 geneials. Anterior larger than the posterior geneials. 



Anatomy. — The hypapophyses on the dorsal vertebrte are 

 continuous throughout the column. On the vertebra above the 

 122nd gasti'ostege the base of the hypapophysis occupies 

 the posterior one-third of the centrum ; the apex is horizontally 

 truncate, and extends a trifle posterior to the vertical of its 

 centrum. The caudal vertebra at the level of the 12th urostege 

 has two triangular hsemapophyses the bases of which occupy the 

 posterior half of the centrum. The inferior zygapophyses are 

 developed as broad wing-like plates, 1*4 mm. long. 



The maxillary bone at the junction of the anterior and middle 

 third is bent inwards at an angle of 45°, and the teeth are 

 arranged in two groups. The first set consists of 7 teeth that 

 are mounted on the anterior one-third of the bone ; the first five 

 are very small and increase in size posteriorly ; the sixth is 

 nearly three times the size of the fifth, and the seventh is larger 

 still, being 1'5 mm. long. These teeth are inclined backwards. 

 The two groups are separated by an interval of 1"5 mm. The 

 second set contains 13 teeth ; the first nine ai^e small and neai-ly 

 equal ; the tenth to the foui'teenth increase rapidly until the last 

 is twice the size of the ninth. These teeth are inclined towards 

 the median line. The anterior tip of the palatine bone reaches 

 the interval between the fifth and sixth maxillary teeth ; there 

 are 16 teeth. 'I'he pterygoid bone bears 19 teeth ; these are on 

 a line that is convex externally; the middle teeth being three 

 times as far from their fellows on the opposite bone as are the 

 teeth at the extremes. The dentary bone is also bent inwards at 

 an angle of 45°, and has the teeth in two groups. The first set 

 is mounted on the inflexed portion of the bone, and consists of 

 6 teeth ; the first to fourth gradually increasing in size ; the 

 fifth and sixth strongly enlarged. The two groups are separated 

 by an interval which is shorter than the sixth tooth. The second 

 set consists of 17 very small teeth. 



Peoc. Zool. Soc— 1913, No. XXIX. 29 



