18 PROCEEDINGS OF THE NATIONAL MUSEUM vol.88 



Family MICROCOTYLIDAE Taschenberg, 1879 

 Genus MICROCOTYLE van Eeneden and Hesse, 1863 



MICROCOTYLE CARANGIS MacCallum 



Microcotyle carangis MacCaxj-um, Zool. Jabrb., vol. 35, pp. 394-396, fig. B, 1913. 



Six trematodes, collected on July 19, 1912, from the gills of the 

 hardtail {Paratractus crysos), agree with the description of this 

 species. 



MICROCOTYLE PORONOTI MacCallum 



Plate 16, Figube 215 

 Microcotyle poronoti MacCat.t.um, Zool. Jabrb., vol. 38, pp. 72, 73, 75, fig. B, 1915. 



Host. — Dollarfish {Poronotus triacanthus) . 



Record of collections. — One, collected July 2, 1907, from gills of 

 host. One (U.S.N.M. No. 8161), collected July 11, 1910, length 4 

 mm., from gills. One, collected July 19, 1910, from gills. 



These trematodes agree closely with the descriptions of this spe- 

 cies. In these specimens, however, the anterior suckers are bilocu- 

 late, a character not noted in M. poronoti. In the two specimens 

 mounted in balsam, one has a distinct costa in each of the anterior 

 suckers ; in the other the costae are indistmct. 



Dimensions in balsam: Length 5 mm.; breadth, at level of ante- 

 rior suckers, 0.22 mm., maximum 0.63 mm.; anterior sucker, length 

 0.07 mm., breadth 0.1 mm.; pharynx, length 0.045 mm.; breadth 

 0.015 mm. ; posterior sucker about 0.054 by 0.09 nma. The length of 

 the sucker-bearing portion is approximately 1.6 mm. 



MICROCOTYLE POMATOMI Goto 



Plate 16, Figukes 216-218 



Microcotyle pomatomi Goto, Journ. Coll. Sci. Imp. Univ. Tokyo, vol. 12, pp. 278, 



279, fig. 27, 1899. 

 Microcotyle sp. Linton, Bull. U. S. Fisb Comm. for 1899, p. 451, figs. 299-306, 



1901. 



Linear-lanceolate; posterior sucker-bearing portion, and middle 

 region of anterior portion colorless or translucent white; margins, 

 including vitellaria, with numerous small black pigment spots. The 

 number of posterior suckers appears to be 90 to 100 on each side. 

 Goto gives the number as about 70. Genital atrium spacious, armed 

 with numerous small recurved hooks. The ovary consists of two por- 

 tions: a small, compact, many-lobed portion, situated ventrally, on 

 the median line, and a larger and much convoluted portion, contain- 

 ing large germ cells, which, beginning at the right dorsal border of 



