After an examination of nine young and eight adult specimens of this species, I am able to make the following observations. In the adults the frontal shield is a little wider than the supraocular, but in the young this difference is hardly noticeable; it varies slightly in length and shape generally, but the remaining characters do not differ to any extent from those noted by Boulenger in his description, In the very young specimens the head appears to be much flatter and more swollen than in the adult, but this is due to the bulging of the eyes, a condition that may be caused by the preservative. In one specimen the frontal is rounded posteriorly and in another sharply pointed, and this would cause a slight difference in its length in comparison with its distance from the snout, the variation throughout the series being from a little longer to one and one-half times as long as its distance from the snout. In another, the frontal is very distorted and is broken up into four distinct shields. As a general rule the frontal is one and one-half times as long as broad, about half as wide again as the supraoculars, longer than its distance from the end of the snout, about as long as the parietals but longer than the suture between them. The internasals are only about half the size of the prefrontals.
The eye is larger than its distance from the mouth. The rostral is about one third broader than deep, the part visible from above being shorter than the suture between the internasals.
In the eight specimens examined the nasal forms a suture with the single preocular. There are two postoculars and six upper labials, though Boulenger noted that there may be six or seven upper labials. There are seven lower labials, three of which are in contact with the anterior chin shields. Scales in 19 rows round the centre of the body; ventrals 131–138; subcaudals 31–41, all single; temporals 2 + 2 or 2 + 3, in one example 2 + 3 on the left side and 3 + 3 on the right.