Biological data are provided for Alliaria petiolata (M. Bieb.) Cavara and Grande (garlic mustard). This weed is found in Victoria, British Columbia, in the St. Lawrence valley of Quebec and in Southern Ontario where it attains maximum abundance in Middlesex County. It is most commonly found in shaded sites: in deciduous woodlands, under hedges and in gardens. When crushed, the aboveground parts exude a strong odor of garlic.

The biology of Canadian weeds. 35. Alliaria petiolata (M. Bieb.) Cavara and Grande.

Seed structure and the taxonomy of the Cruciferae

Taxonomy and phylogeny of the benthic Prorocentrum species (Dinophyceae)—A proposal and review

Seed Coat Microsculpturing in Brassica and Allied Genera (Subtribes Brassicinae, Raphaninae, Moricandiinae)

Silicosis — Continued Silicosis is a chronic lung disease associated with the inhalation and pulmonary deposition of dust that contains crystalline silica. Through the Sentinel Event Notification System for Occupational Risks (SENSOR)* program, CDC's National Institute for Occupational Safety and Health (NIOSH) is assessing practical models for implementing state-based surveillance of silicosis and linking follow-up intervention activities to surveillance reports. From 1989 through 1992, the Ohio Department of Health (ODH) SENSOR program identified silicosis cases through reports of Bureau of Workers' Compensation (BWC) claims, physician reports, and death certificates. The addition in 1993 of hospital discharge reports as an ascertainment source resulted in a substantial increase in the number of silicosis case reports identified annually (Table 1). This report describes the investigation of a case of occupational silicosis in Ohio and summarizes the impact of hospital-based reporting on surveillance for silicosis in Case Report In September 1991, a case report † was sent to ODH by an infectious disease specialist who was treating a 55-year-old sandblaster with advanced silicosis and an associated Mycobacterium kansasii infection § (2). In January 1992, NIOSH and ODH conducted a joint investigation at the worker's place of employment—a metal preparation shop—to evaluate current levels of exposure to respirable crystalline silica and to screen co-workers for silicosis. The investigation detected excessive exposures to respirable crystalline silica (2–5). Chest radiology revealed radiographic abnormalities consistent with pneumoconiosis in four of 16 current and former workers *SENSOR is a program of cooperative agreements with state health departments to develop surveillance and intervention strategies for selected occupational conditions. The National Institute for Occupational Safety and Health currently supports SENSOR silicosis programs in seven states and Wisconsin). † Case reports should be submitted for persons with a physician's provisional diagnosis of silicosis, a chest radiograph interpreted as consistent with silicosis, or pathologic findings consistent with silicosis (1).

Margaret R. Murley

Papers

Seeds of the Cruciferae of northeastern North America