60 



in long axis 0.14 mm., and in short axis 0.06 mm. Looking 

 into the mouth, it seems to be surrounded by a row of fine 

 spines, directed inwardly and toward the centre (the appear- 

 ance may, however, be given by the bordering prism-like 

 cells). Within the mouth cavity (Figs. 2 and 3), springing 

 from the base and apparently set in the chitinous ring about 

 the esophageal opening, is an armature of three complexly 

 curved chitinous plates. Esophagus 0.75 mm. long, flask- 

 shaped, 0.25 mm. in diameter in its posterior and thicker 

 part. At level of second third of esophagus, 0.65 mm. from 

 front of head, on each side a pointed papilla projects above 

 the cuticular surface (opening of cervical glands). No 

 esophageal bulb. Intestine straight. Anus (Fig. 4, a) 

 subterminal (0.14 mm. from tip of tail). Vulva (Fig. 4, b) 

 prominent, provided with thick circular lip, 0.65 mm. anterior 

 to tip of tail. Ova (Fig. 5) slightly yellowish, segmented, 

 oval, with thin, colorless, unmarked wall, each with a slight 

 thickening or tubercle at one pole; measure 0.064 to 0.07 mm. 

 in length and 0.038 to 0.04 mm. in width. 



Spiroptera incerta, n. s. (Plate IX). 



Among all the types of verminous parasites derived from 

 animals in the Zoological Gardens in the series studied by 

 the writers by far the most numerous group has been made up 

 of a small nematode obtained from the proventricles of a 

 number of the inhabitants of the bird house, in which it 

 would seem that a well-marked and strictly localized endemic 

 has been for the past year or two, and is now, prevailing. 

 The material studied (Path. Hist., 1109, 1120, 1453, 1463, 

 1613, 1616, 1618, 1619, 1620,1621, 1622, 1623, 1624, 1625, 

 1626, 1627, 1628, 1629, 1630, 1631, 1644, 1661, 1672, 1675, 

 1686) includes examples obtained at autopsy from twenty- 

 five birds, the parasites invariably occupying the proventricle 

 and some times also being found in small numbers in the 

 gizzard. The specimens, while often found free in the mass 



