Orthotropous growth

FIGURE 5.1 Habit of a typical plant of Calyptrochaeta remotifolia (Mull. Hal.) Z. Iwats., B.C. Tan Touw (orthotropic type of growth pattern) showing a bundle of + equally long, radiating axes connected at the base... 

Morphological Differences between the Orthotropic and Plagiotropic Types of Growth Pattern in Calyptrochaeta Species from the Malesian Region Including a List of Species for Both Types of Growth Pattern... 

Equally long orthotropic axes Sympodial growth... 

Calyptrochaeta remotifolia (Mull. Hal.) Z. Iwats., B.C. Tan Touw is the most common and widespread Calyptrochaeta species in Malesia and shows the orthotropic type of growth pattern. Fleischer (1908) reported it growing on rotting bark and dead branches, on soil, and rarely on rocks. Fleischer s habitat description indicates that C. remotifolia occurs in drier habitats than C. ramosa or C. parvireta, but the first author of this paper observed occasionally herbarium specimens of C. remotifolia intermingled with C. ramosa, C. parvireta, or both. 

Second, the growth process allows a variety of routes to the formation of fibers but there are no simple way s to form a dense isotropic plastic. Thus, even essentially isotropic materials will have a fibrous composite microstmcture. Weiner et al. (2000) have argued that many biological structures can be viewed as a search for isotropic properties, or at least orthotropic properties (strong in two dimensions), from fibrous materials. This would reflect the unpredictability of stresses encountered by a structure in a dynamic environment. 

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