The effects of the anthelmintic drugs, praziquantel (PZQ) and bithionol (BT), on the gastrodermis of the lung fluke, Paragonimus ohirai adults were observed in vitro and in vivo. The gastrodermis of the worm treated with PZQ in vitro showed an increase in the number of autophagic vacuoles, most of which enclosed cytoplasmic elements, and multivesicular bodies. In vivo, myelin-like membranous bodies were observed. Autophagic vacuoles appeared as residual bodies near the luminal surface of the cells. Abnormal Golgi complexes with dense cisternae were seen on day 3-7 post-treatment. Rough endoplasmic reticulum was linear, reduced in size and numbers and partly disintegrated. The gastrodermis of the worm treated with BT in vitro showed considerable variety of damage. The tall, columnar cells in the secretory phase were swollen and vacuolated. Short, dense, pyramidal cells in the absorptive phase appeared to be normal. Active phagocytosis was observed at the luminal surface of the gastrodermis after 3 hr of incubation. Autophagic vacuoles and membranous whorls or vesicles were seen in the cells. Cellular breakdown was pronounced after 3 hr of incubation. In vivo, autophagic vacuoles were present near the apex of the cells. Cellular breakdown was conspicuous on day 7 post-treatment. These results suggest that autolytic breakdown of the gastrodermis induced by both drugs probably contributed to the eventual death of the parasite.

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Matsuda S (Department of Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, Japan, Yahatanishi-ku, Kitakyushu, 807, Japan). Seasonal variation of births in a locality of Hochiminh city, Vietnam
Seasonal variations of births in a community of Hochiminh city, Vietnam are analyzed by a Kolmogorov-Smirnov type statistics.<BR.The excess in births is observed in the latter part of the year, but there is a difference in the timing of the peak of the first and subsequent births, that is, July to August for the first births and September and November for the subsequent births. This fact suggests that associated factors are different between the two parity groups. It does not seem that marriages and the lunar new-year holidays are important enough to create seasonal variations in conception in this population.
On the other hand, the traditional social belief of reproductive activity seems to play some role in creating the seasonality in births. And temperature hypothesis is also plausible for this population.

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A new blackfly species, Simulium (Gomphostilbia) hiroshii sp. nov. is described based on female, male, pupal and larval specimens collected from the Solomon Islands, South Pacific. This species possesses several characters which are unusual for the subgenus Gomphostilbia as follows : in adults, basal part of the radius fully haired in the female but bare in the male, female frons almost bare and shiny, female tergites 5-8 shiny, male genitalia lacking parameral hooks; in the pupal stage, 4 respiratory filaments per side, sterna 6 and 7 devoid of outer hook on each side; larval hypostomium with serrate lateral margins, and larval body with a large conical protuberance dorsomedially on abdominal segment 7, as well as paired dorsolateral small protuberances on abdominal segments 1-4 and metathoracic segment. This is a first record of the subgenus Gomphostilbia from the Solomon Islands and represents the most easterly geographical distribution of the subgenus.

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