Supplement 

 DATA ON THE DEVELOPMENT OF MONOGENETIC TRElvlATODES 



Below is expressed all the information at our disposal on the p. 138 



development of separate species and genera of monogerietic trematodes 

 from literature as well as that based on our studies. The naain attention 

 is directed to the structure of the larvae and the development of chitinous 

 elements of the attaching disc which have, as has already been indicated, 

 important significance in the systematics of the group. The data on the 

 development of separate species are preceded by short descriptions of the 

 structure of adult animals which aids the understanding of the peculiarities 

 of development. The data on the developnnent of the viviparous genus 

 Gyrodactylus Nordm. are not included (see page 92 ). 



1. The development of Acolpenteron , Fischthal and Allison 



In 1940, Fischthal and Allison (Fischthal and Allison) described 

 Acolpenteron ureteroecetes --a new genus and species of the simply organ- 

 ized monogenetic trematodes parasitizing the ureters of fresh water fishes 

 of North America. A year later they also described the second species of 

 the genus A. catostomi and gave succinct data on its development adding a 

 drawing of the free -swimming larva. The adult Acolpenteron (Fig. 44) has 

 an attaching disc which is weakly-delineated from the rest of the body. It 

 is equipped with 14 edge hooks of the type usual for Dactylogyridae with the 

 widened part of the upper handle. There is no other armature on this disc 

 besides these hooks. E. V. Gvozdev (1945), who described a third type 

 from Kazak SSR (regions surrounding Alma-Ata) indicates that worms of 

 this species are located freely in the lumen of the ureters. The absence of 

 pigmented little eyes ds characteristic for representatives of this genus, 

 more precisely their degeneration, for on the anterior end of the body in 

 front of the pharynx there is a considerable number of pigmented seeds 

 lying in scattered fashion in the parenchyma. The anterior end of the body 



with two weakly expressed head growths, with the sensitive hairs (?) and 

 with the ducts of the head glands opening into these growths. The digestive 

 system has a rounded pharynx and two straight intestinal trunks nnerging 

 at the posterior end of the body. The sex complex lies at the center of the 

 body between the intestinal trunks. The eggs of A. catostomi (Fig. 135) 

 are deposited in the ureters of the host and are discharged with the urine 

 into the water and develop on the bottom. The authors indicate that 

 cleavage takes place only after the eggs reach the water and that all the embry- 

 onic development takes place within 6-9 days. At the end of this period a 

 free-swimming larva (Fig. 136) emerges from the egg. This larva is 

 0. 123 millimeters long and 0. 040 mm wide, and is equipped with ciliary P* ^^^ 



epithelium located in four groups of cells. One of these groups is located 



146 



